Yet ANOTHER "security light" thread.... except...

I am completely overhauling this initial post so that people can understand what this thread is about...

There IS a fix if you have had or currently are experiencing problems with your car not starting because of the "Security" light coming on. This will even deal with what you can do to possibly start your car so that you can fix the problem. (Note: that might not always work in some cases.)


The following instructions are written SPECIFICALLY for a Chevy Impala that use the Passlock II system. HOWEVER, these instructions are good for ALL GM vehicles, the only difference is that the diagrams will probably be slightly different.


This thread will also deal with what to do if you are experiencing "weird" strobing or flashing lights in your car at random times. Some people have also experienced the following symptoms:


-Random lights flashing on and off.
-Traction control light turning on and off randomly.
-Power windows / Power locks not working randomly.
-Lights inside the car flickering.
-Fog lights turning on and off by themselves.
-Hearing "clicking" sounds by the fuse box in conjunction with random lights.



I will try and have kind of a running wiki in this first post to help people with getting into the specific post that they need for the problem they're having.



What to do if you're having problems with the security light coming on, but your car still runs fine. (http://www.automotiveforums.com/vbulletin/showpost.php?p=5841025&postcount=35)



What to do if you're having problems with the security light coming on AND your car does not start, or does not start intermittently.

1)First, try the SECURITY RELEARN PROCEDURE in this link (http://www.automotiveforums.com/vbulletin/showpost.php?p=5823599&postcount=4)


2)If above does not work, try this - clean out your ignition switch. (http://www.automotiveforums.com/vbulletin/showpost.php?p=5841025&postcount=35)


3)If cleaning out your ignition switch does not work, you may have to do the following - in some cases possibly ALL THREE:

a) Do the "Bypass Method (http://www.automotiveforums.com/vbulletin/t698860.html)". (Thanks to Ponchonutty)

b) Replace your ignition cylinder. Here is a quick guide on how you can do this yourself. (http://www.2carpros.com/forum/2000-chevy-impala-ignition-switch-issues-vt68221.html) (Just a quick FYI if you're going to replace your own ignition cylinder). (http://www.automotiveforums.com/vbulletin/showpost.php?p=5839732&postcount=31)

c) If you have an aftermarket alarm system (ie. remote start)... You will probably have to remove the entire board and RESPLICE the wiring correctly.

For those attempting to do the above themselves this diagram (http://www.bulldogsecurity.com/bdnew/newsite/pictures/instdiagrams/46.jpg)shows you a picture of all the wires and how remote starts generally work. Do this ONLY if you know what you're doing.



4) If you've done ALL of the above - and it still doesn't work, I recommend changing your BCM. Here is a picture of a BCM on an Impala (http://www.automotiveforums.com/vbulletin/showpost.php?p=5822452&postcount=2) - and the post will also tell you where to get to it to replace it. (Thanks to HeMi101)

(A WORD OF CAUTION ON REPLACING YOUR BCM: Since the new BCM has to be programmed with the new BCM already installed in the vehicle - you will not be able to install the new BCM and drive it. It will have to be programmed before your car will start)






If you are having weird issues with you car, like the automatic doors/windows won't work. Lights flickering, etc.. More than likely, your BCM is bad or going bad. Do option number 4 above.




Good Luck, and I hope this helps people.

Well someone correct me if im wrong, but couldn't you get a used Ignition w/ a key for cheap just to test, and swap them out, do a sec. relearn and BANG you'll know if it fixes it or not?

Anyways,
As soon as anyone says they have the "Service Vehicle Soon" light on the message center, I know something BCM related is not working and every time i see people say random lights are coming up, 80% of the time it IS a bad BCM.

Here is what a BCM looks like:
http://i16.ebayimg.com/01/i/001/0a/41/90ef_1.JPG

And its not hard to locate. you really don't need a picture or a diagram.
Pull down the black Kick cover (2 little clips that you push) under the driver side of the dash, and its above (but slightly towards the front of the car) the Parking brake pedal. If i remember correctly, you'll see the three connectors connected to it (Grey, Grey and Pink) and the black clip that holds it to a metal bracket. I'll see if i can find any pictures, but should be findable from the description above. All i was told the first time was "above the parking brake" and i found it.

You can have it programed by any shop with a Tech II Programmer, not just a dealer. COULD be cheaper (was 50$ to program ours at our usual Mechanic's shop vs 140$ for programming at the dealer we bought it from).

One place to look is Rock Auto:
http://www.rockauto.com/catalog/x,carcode,1384084,parttype,2888

But there is many other places.

Hemi, thanks for the info...

I went to the website you linked to, and it has about 4 different ones... Does it matter which type I get? Are the only differences between them is their manufacturer, or is it for different type of vehicles?


Also, are these remanufactured? If so (which isn't a problem for me) - can they be programmed... Cuz from what I understand is that used ones can not be reprogrammed, but I'm thinking remanufactured ones can???






So far you're ahead $20.... unless someone can find them cheaper.... Though you've got $10 at the minimum hemi; thanks!





BTW - I've heard a million times about the relearn sequence... and every time I read a different post, the process is a little bit different...


Does anybody know the actual relearn sequence?

I thought all were the same, but by their listing 9C1's (Police Package) had different ones.

I'm pretty sure you want either "ACDELCO Part # 21812285, $131.89" or "A-1 CARDONE Part # 730320 $89.79".

Gmpartsdirect.com has them listed at $118.07 and I believe they are a dealership selling parts online, so that SHOULD be a brand new ACDLECO part at that price. http://www.gmpartsdirect.com/catalog/frameset.cfm And choose 01/Chevy(geo)/Impala and search for body control module. I tried to get a direct link but no dice.

Also Check your PMs cuz i sent you one.


And What they mean by manufactured is they made sure the boards were good, and replaced the P-ROM that contains your RPOs and Serial #, so ya its blank and ready for programming.

As far as security Relearns go, This is the one we have stickied at another Impala Website.

Introduction

Here are the directions for doing a security relearn.

Procedure

Make sure you follow this procedure to completion for correct operation. The doors and trunk must remain closed for the entire procedure

Properly executed, this procedure should take approximately 35 minutes to complete.

1. Attempt to start the car by turning the key to the Start/Run Position.

2. Observe that the vehicle fails to start and that the security light is illuminated.

3. Release key to the 'ON/Accessory' Position. (DO NOT turn key to the 'off' position.)

4. Allow the vehicle to sit with the key in the 'ON/Accessory' Position for no less than 11 minutes. At the end of the 11 minutes, the security light will shut off

5. Turn key to off position and allow the vehicle to remain in the 'OFF' position for no less than 30 seconds.

6. Repeat #1 - #5 for 3 cycles. 7. On 4th attempt, car should start.

NOTE : Since this is a fairly long procedure, it's a good idea to limit all electrical sources, such as disconnecting headlights, to prevent discharge of battery.

NOTE 2 : It is OK to wait LONGER than the allotted time, but it is not safe to wait less time. I.e. 12 minutes instead of 11 minutes should be OK; however, waiting 10 minutes instead of 11 minutes will result in a failed security relearn.

Alright Hemi...


I think I got it! I'm holding the BCM in my hands right now as a matter of fact... :D yay!


Thanks for all the info. I decided to also replace the ignition switch on it, I figured I might as well kill two birds with one stone...


It was funny, because I went down to take the bcm out and I noticed that one of the wires was damaged pretty good like not even an inch out of one of the pins... So I had a HELL of a time trying to splice that faaaacker back together, but I think I got it.


I hope to all heck that this works because I'm tired of just looking at my POS car in the garage... It would be nice to be able to actually drive it.




Its funny, I talked to one of my friends who also has same year Impala... And they started getting the security light as well. I informed him of all the fun stuff I'm doing... yay.

the Security Light it self doesn't mean He's gonna have BCM problems, but I do foresee a new Ignition in the future! :lol: I've had the Security Light come up as often as 3 - 4 times a week for the last year and a half and no problems yet Knock on wood.

Now here's another question Hemi...

I'm looking at my ignition switch AND cylinder... Do you think I ought to change the cylinder or just the switch... (cuz they both run about $100 a pop)... Cuz the cylinder (the key) works fine, but I figured I ought to probably change out the switch at least.

And since I now have to (I screwed up the switch, but the cylinder is still fine) I know I have to replace at least that. But oh well. I figure the cylinder is fine, just maybe the switch was the problem?

Now here's another question Hemi...

I'm looking at my ignition switch AND cylinder... Do you think I ought to change the cylinder or just the switch... (cuz they both run about $100 a pop)... Cuz the cylinder (the key) works fine, but I figured I ought to probably change out the switch at least.

And since I now have to (I screwed up the switch, but the cylinder is still fine) I know I have to replace at least that. But oh well. I figure the cylinder is fine, just maybe the switch was the problem?

Well Start Cheap as you can. Got no choice but to change the switch now, Remember the procedure and worst comes to worst You end up having get new Cylinder.

I don't know too much about the ignitions, I'd think the switch part (Which is the actual electric part of the ignition) Would be the one that would wear out and mess up Passlock. To me The Cylinder is just a metal Lock cylinder, They'd wear out and your key wouldn't work.

Just wanted to mention here that I've had the SECURITY light problem with my '02 Impala (3.4 111k) off and on for about 1.5 years now. Up until recently, the message would appear, but the car only failed to start once. A month ago, I drove the car 900 miles, spent two weeks, then drove another 900 miles. Amazingly, during this two week period, the SECURITY light came on numerous times and the car refused to start THREE times!!! But here we are a month later, and no Security light, and the car has started every day fine. Was it just coincidence that I experienced this unprecedented high failure rate in this short two-week period, or is this a clue as to what sets this problem off? Could it be the keys dangling from the cylinder for an extended period of time? Maybe it has something to do with temperature - either ambient or the car itself?

Personally, I think it's the ignition swith and/or cylinder - but I haven't replaced it yet. I've read a lot of posts talking about the resistance "fix", but I've also heard of follow-up failures, so I'm skeptical that this really corrects the problem. But I'd really LIKE to fix this because the car cannot be trusted (even though I trusted it enough to drive it 1800 miles recently). The 10-minute wait is bad enough, but my fear is the car eventually won't start AT ALL - and who knows where I'll be when THAT happens...

How many people out there have replaced the ignition switch and/or cylinder and had the problem re-occur??? I haven't seen any statistics on that...

90% of the time the whole security light issure is caused by the ignition wearing out. And Technically age and millage doesn't have that much to do with it, its how often the car is turned off and on so it can really happen at any millage.

Well to add another twist to this idea of what is wrong I had a customer call with simular problems. Thinking it was a PK2 failure I set out to bypass the sytsem. Upon further inspection I noticed that not all of the gauges worked properly when it wouldn't start. I then banged on the steering column when cranking but that didn't work. Then I did the same on the dash and it started! Traced it down to a bad circuit inside the cluster. Put a new cluster in and it was fine.

Well to add another twist to this idea of what is wrong I had a customer call with simular problems. Thinking it was a PK2 failure I set out to bypass the sytsem. Upon further inspection I noticed that not all of the gauges worked properly when it wouldn't start. I then banged on the steering column when cranking but that didn't work. Then I did the same on the dash and it started! Traced it down to a bad circuit inside the cluster. Put a new cluster in and it was fine.

Trust me, if that was the problem I would have LONG fixed it by now... Ever since it started doing this, I dunno how many times I would just beat the living shi$ out of that car.... and 99% was just for the hell of it.

I think all Chevy's, Fords, you name it - if its a domestic car, its a POS... I know a some of you will disagree, but In the last 11 cars I had, I owned 2 foreign made cars. One Honda, and a Toyota (before they started manufacturing them in the US)... Never had a problem with either one..... And when I say never, I mean I owned both cars for 2 years each. I am a dumba$$ for selling them.

Worst mistakes of my life was to buy a Chevy or a Ford. That same mistake will never ever happen again. I'm gonna fix the problem, but if anything major comes up in either Chevy I own, pitch both of them and buy two Hondas or something.

Well, I'll let you know that I work on ALL makes and models right on brand new vehicles. Many times I wrench on them before the customer ever even drives them. Today, just about all car makers are the same in quality. I've had problems with 2008 Hondas here lately!!!! I will state though that GM has had their fair share of PK2 and PK3 issues!!!!

Well to add another twist to this idea of what is wrong I had a customer call with simular problems. Thinking it was a PK2 failure I set out to bypass the sytsem. Upon further inspection I noticed that not all of the gauges worked properly when it wouldn't start. I then banged on the steering column when cranking but that didn't work. Then I did the same on the dash and it started! Traced it down to a bad circuit inside the cluster. Put a new cluster in and it was fine.

Was it an impala? Weird that the cluster would stop it from starting. I had one that had a cluster with a short (cluster wouldn't work) but the car still worked. And doesn't make Much difference, but 00-05 Impala have Passlock II not passkey.

My Imp will start and run great even without the cluster installed...

Talking about "cluster"-farks... I have updates on my situation.


So I get the new BCM, install it - I get the new switch, install it. I decided NOT to get a new cylinder (epic failure on my part). Installed everything, etc, yada yada. I also found a wire going to the BCM harness that was slightly damaged... fixed that.


Call around to see who can program the BCM the cheapest. Ends up being a Chevy dealer here in town. The only catch is, the car has to be there for them to program it...


GREAT, so I had to pay to get it towed there. I get that done, I tell them whats up. They say, no prob. About 2 hours into it, the guy comes back and tells me, they flashed the BCM fine, but it still won't start, and KP2 light is still on. I said, prob. the cylinder; and at this point the mech. also informed me that the PK2 sensor is actually built into the cylinder NOT the switch (as I had incorrectly assumed).

So after replacing them screwing w/ it for 6 hours and a cylinder later... The car starts, BUT PK2 light is still on.


At this point, they schlep the car back to me saying that "one of my connections is wrong, replace the connectors on some wires, etc... and bring it back so they can clear the codes; because something was giving very high resistance."


At this point I can see whats going on, they just want me to get the heck out of there because it was closing time. I was thinking "BS", but - anywhom. I take the car back, sauder the three connections going into the switch, and STILL picking up high resistance on the PK2 wire ignition siwtch side...


Took me a day, but got to thinking about it, that there is NO way that I was having wiring issues because before I changed out anything, there was no resistance showing when the car was off. So I knew that it had to have been something that was replaced.







Well, whatdya know. I had my meter on the whole time, and the first thing I took out with the meter on was the "newly installed" cylinder... BAM, immediately took the reistance off as soon as I pulled the cylinder out.


I called them up, told them that their mech. was a moron for not checking the "new" part he just installed and told them that I expected them to work on and replace the cylinder for free. The service manager threw a little bit of "resistance" about it (no pun intended) - but I told him that if I get charged as much as a penny, I would charge them the same amt. charged to me for having to troubleshooting the parts the I paid for them to install in the first place.


He quickly changed his tune.


I will find out on Monday (though I dunno for the life of me why it would take more than 15 min. to change out a cylinder and do a manual relearn) - but at this point I don't care...


This SHOULD fix the problem.


BTW - even tho the PK2 light is still on, I am happy to say that replacing the BCM cleared up ALL the problems w/ flickering lights, etc.


To generalize the problems here that I originally had... Bad BCM, and bad ignition cylinder.






To ALL the people out there having this very same problem... DO THE "RESISTANCE BYPASS" first!

2nd - if that fails, get your ignition cylinder replaced (At a dealer, this will cost you apx $200 + labor... If you do it yourself, you can get a new cylinder for apx $100 +-$10-20)

If you're still having problems, change your BCM out. I was able to buy a reman. BCM for $150 (I also got a credit for returning the old BCM, so really I only spent like $80 on the new BCM). If you get it programmed at the dealership they will prob. just charge your labor to flash the new BCM. (And if you learn by my mistake, it is a good idea to change the BCM AFTER the car is already at wherever you're getting the new BCM flashed - as you will not be able to drive the car if you switch out the BCM)


Altogether IF you decide to do this yourself - expect to pay APX. $150 (new BCM) + $100 (BCM reprogram) + $100 (new cylinder) = $350



BE CAREFUL! Do NOT trust that any "new" component is automatically "good" just because its out of the box...

I had to make the dealer mechanic feel like a complete idiot because I sat there and showed him that the very part this "ASE CERTIFIED" mechanic just replaced was bad, and a regular everyday non-ASE certified guy had to troubleshoot HIS work.


If you are wanting the dealership to do all this work (as I had described above), EXPECT to pay anywhere from $800 to over $1000 (and this is IF the guy knows what he's doing). If you figure that they charged me $200 JUST for the cylinder - and $300 for the labor, you know they're gonna bend you over if they have to replace the BCM as well...











That's it, I will let you guys know what happens on Monday when I get the car back - but this SHOULD work.

Also, forgot to mention.

IF this entire thing I just went through works out. I will post DETAILED instructions on how to:

1) Change out the BCM, and the best way to get to your BCM (they are HARD to get to, but this little technique I know will get you in and out in like a minute)

2) How to get to and change your cylinder.

It'll be interesting to see how it works out for you, but how will you know if the problem has been solved? Won't it be weeks (or even months) before you'll be sure? With my Impala ('02, bought new, 111k), I hadn't had a "no-start" SECURITY problem in about a YEAR before I took a long trip and had it happen (at least) THREE times in two weeks!!! This HAS to be a clue as to what the problem is ...

Yep. Too bad you didn't try the resistor trick first. Yes the "code" part of the system is inside the lock itself. That's why if a crook rams a lag bolt in it via cordless drill it'll break it making it unable to start. That's also why super long and heavy keychains mess up these system too.

It'll be interesting to see how it works out for you, but how will you know if the problem has been solved? Won't it be weeks (or even months) before you'll be sure?

Yes, I've already anticipated someone asking me this.

The answer is: It should undoubtedly return when either the BCM, or the cylinder fail (or start to fail) again. As a matter of fact I expect it to return, BUT hopefully not anytime soon.

Now, unless you happen to be one of those unlucky bastages that actually happen to have problems w/ a wire or something - sucky deal, that is the absolute worst case scenario...


BUT, more ofthen than not it is some sort of board or mechanical failure... So you start changing things one by one, it will (should) fix the problems... lol

Alright guys, here is the semi-short of it...



Got the car back today, I don't have a lot of time to post the specifics on here, but ends up being that the cylinder WAS bad - BUT (to throw another friggin curveball into it) - my aftermarket remote start/security system was also the culprit... This was taken out, and poof - no more security light.

And btw - you can't just "take out the control board", you actually have to splice the wiring back up...


So in my case; I had almost the worst case scenario (besides a wire going bad somewhere). Almost every component that had anything to do w/ the PK2 system (and how it works based on resistance) completely failed.

In review, here are the list of things I had to do to my vehicle:

-BCM change and flash new BCM
-Ignition switch change.... (although you probably WONT have to do this, I just replaced it because I wanted every component in there that had anything to do w/ the PK2 to be new)
-Ignition cylinder replace.
-Remote starter/aftermarket security system had to be completely bypassed.



Not everyone will prob. have to change out their BCM - but in my case that's what was causing all the lights flickering and general "body function" failures.




If you want your security light to go off, I would do things in the following order:

1) Do the resistance bypass method...
-IF your car already has an aftermarket alarm system or a remote starter, chances are you probably already have a bypass installed.


2) Change out your ignition cylinder. (The passlock sensor is inside this cylinder - sometimes, like in my case, they completely fail)


3) If you already have a remote starter installed AND have a bypass (which those two will prob. go hand in hand) - BYPASS the entire aftermarket security/remote starter system. You can't just unplug it - you will have to re-splice the wiring as well.


4) If that still didn't fix the problem, replace your BCM - this is actually cheaper than you think to do.




If you let a dealer do all this, expect to pay over $1500 easy, but you can do it yourself for not a 1/5th of the cost...











Security light gone ladies and gents, and just to make sure you guys understand... At some point - in theory anywho - the chances are good that those whom not had this problem before on their car, will eventually have this problem. I DO EXPECT mine to possibly come back, but when it does I have a game plan. As a matter of fact, I know the underside of a Chevy better than the back of my hand now....



Good luck.

Your a jinx or something Celery. I've been getting my Security light every 3rd time i start my car, and its startin to Bother and worry me. But I'm probably gonna buy used Cylinder with its key for ~25$ from a wrecker when it happens, so it's all good, as long as my remote entry works. :biggrin:

And yes there are some problems like the passkey and that, that WILL return. But It should be a good 60 or 70K Miles before that happens. Long as you don't do alot of disconnecting the battery, or have to jump start it often, I would doubt your BCM problem will come back. Could even be, if your Remote start was a problem, maybe it was installed wrong or very crappily, and that IT Caused that problem. so with it bypassed, Again shouldn't happen.

Covert, you never stated that you had a remote starter installed. A well built and properly installed remote start should never have caused the issues you stated. I've been doing remote starts for over 13 years now and have yet to see a remote start cause this. I have however, seen the install be the root of the cause of problems. Even if a botched install, I'd would like to know what conclusion came about stating that the bypass was the issue.

Covert, you never stated that you had a remote starter installed. A well built and properly installed remote start should never have caused the issues you stated. I've been doing remote starts for over 13 years now and have yet to see a remote start cause this. I have however, seen the install be the root of the cause of problems. Even if a botched install, I'd would like to know what conclusion came about stating that the bypass was the issue.

Poncho, let me stress that the problem was NOT the wiring with the remote start. The circuit board on the aftermarket alarm system started throwing high resistance. I know this because I myself kept the module after they took it out. After inspecting the circuitry boards, it seemed that it was due to either faulty capacitors and/or resistors on the board itself.

And just so its clear, the "bypass" was not the issue at all. The bypass module was installed and working correctly, but the bypass module and the aftermarket alarm were actually two different modules (circuit boards). So essentially they could have just left the bypass on there, but they decided to remove it as well just to ensure that there was nothing aftermarket on it... And I didn't have a problem at all with that, because if I ever need to do the bypass again on it, I could easily splice one back in. Just FYI: It was an model "ASPASSIII" (the bypass module).


We need to ask the mods to make this a sticky thread, because this happens ALL too often, and there does not seem to be a "definitive" guide. And trust me, from what I've gone through - I decided to dwell DEEP into this issue and make sure and get this resolved.

As a matter of fact, one of the guys that I attend church with has same type of vehicle, and guess what: PK2 light issues as well. I told him he was in luck, because I know what to do. In his case, he only had to replace ign. cylinder and BCM. He got all that done for apx. $200 - and no PK2 light (btw - he was starting to have random light flickering issues as well, and that's what tipped me off to possible BCM problem).

But just a quick report, since the whole incident being finally "resolved" apx. 2 weeks ago. The Impala has had no PK2 lights, and everything works like an absolute charm - like its supposed to... Yes, ladies and gentlemen - Chevy's can start and run, but sometimes its at a cost to you.

I also wanted to personally thank you Poncho and Hemi for all the good insights into this problem.

I hope that the admins could possibly STICKY THIS THREAD so that other users that have this very same problem have some sort of refference to be able to jump to without having to look through TONS of threads to piece together the answers.

I mean I litteraly had to research this problem for at least 2-3 weeks and try to put the puzzles together to finally figure out where I needed to check and to start, and what I needed to do and look out for. I mean I had to go through at least one huge thread about this PK2 light that was apx. 20 pages long and try to puzzle together all the pieces from those 20 pages.

PLEASE MODS, MAKE THIS A STICKY SO THAT OTHER PEOPLE DONT GO INSANE! THE THINGS MENTIONED IN THIS THREAD ARE ALL VIABLE FIXES FOR THIS PASSLOCK 2 ISSUE THAT A LOT OF PEOPLE ARE EXPERIENCING AND KEEP STARTING NEW THREADS ABOUT.

No problem. I'm just glad you got it back on the road.

Just wanna throw one thing in if it was to get stickied (I don't know if its been said in this thread anywhere), don't suddenly think your ignition switch needs replacing. Try cleaning your ignition and try your spare key for a week or 2, as a worn key causes the message too.

I've had problems with getting key cut right, so i got sick of this one sided key (only works if a certain side of the key is pointed up.) so i switched to another key, and no PL2 message for bout a week now.

a good sign that your ignition might be going is: At night, the courtesy lights don't come on when you pull your key out or if you jiggle your key with your door open, and it stops dinging.

Over a year went by with no SECURITY light or starting problems, then a long road trip and three failures in two weeks, and now over two months removed from the long trip and no failures or lights again.

No remote starter or any other aftermarket stuff on my car. No cluster problems or other weird stuff going on with my car. Car was also purchase brand new and has never been touched in 112k miles now by anyone other than me and the workers at the Chevy plant.

CovertCelery :

Your car may be "fixed", but how do you know which part was the problem if you changed everything out at the same time?

I wish I had the tools to debug this problem myself. Probably could figure it out very definitively in less than one day.

Colt, Could of been a dirty key (dropped it or got something on it) and caused problems. Then dirt rubbed off the key and presto no problems right now.

& I Will Gareentee replacing the Ignition Cylinder is what fixed his PKII messages, and the BCM fixed the stupid light problems he was having.

I don't think it was a dirty key. The failures that occurred during that long road trip occurred with two different keys. If I end up doing ANYTHING at all to correct this problem, it'll probably be a new ignition switch. Then, I'll have to wait another year or more to be reasonably sure the problem is gone because it happens so infrequently with my car.

I just wish I could look at the stupid program loaded in the computer and debug the problem backward to the source...

I don't think it was a dirty key. The failures that occurred during that long road trip occurred with two different keys. If I end up doing ANYTHING at all to correct this problem, it'll probably be a new ignition switch. Then, I'll have to wait another year or more to be reasonably sure the problem is gone because it happens so infrequently with my car.

I just wish I could look at the stupid program loaded in the computer and debug the problem backward to the source...

Colt, to make absolutely sure we are talking about the same things here... Your ign. switch and ign. cylinder are two different things. The cylinder goes into the switch... But I seriously doubt that your switch is the problem, cuz the PK2 sensor is built into the cylinder. So if you are thinking about replacing anything, I'd go w/ the cylinder first.


And to let you know, I did go step by step by step on my PK2 issue. Obviously it wasn't "just" a PK2 issue, but other stuff too. I would say that, unless you're having any other weird or funky issues, do the following:


Check and see if you might be able to "clean out" your existing cylinder. That could potentially work, and will enable you to save money by not having to replace the cylinder.



The second thing I would try (if you're looking at trying to get the cheapest fix possible) - is to do the bypass method.



I know for a fact that ponchonutty has a thread somewhere around that tells you EXACTLY how to do the bypass method. (I will PM him and see if he is either will to share it again in this thread, or post a linky to one of his old threads that dealt with the bypass method)... This info is kind of "spread" all over the place in this forum. (Shoot it took me a good month to get all the info collected and put together for me to even try to figure out where I should start)... The bypass option will take some elbow grease, but the parts are cheap to get. $10 at most...



The last thing is to go ahead and just replace the ign. cylinder. Slightly costier option, but I have a feeling that more often than not - the cylinder is prob. going to be at fault for this PK2 issue. (Just FYI to all the ppl thinking about doing this, you have two options: 1) buy a new cylinder, that comes with new set of keys... But then you will have two sets of keys, one for your doors/trunk and another for your ign. 2) Get the ign cylinder re-keyed to fit the existing keys. A dealer can do this for you as well, but I've heard on here that a locksmith can do it as well... The latter prob. being the cheapest option)




IF at this point you're still having the PK2 issue, the only two things left are either an aftermarket alarm that you don't know about (but is still connected or something), or your BCM... And I'm not saying that it can't "just" be your BCM, but I'm just trying to give you a list of options to start with that require little or no money at all to try to do first, before you go and start changing out BCMs and stuff...



Hope that helps - this should get rid of your Security light (Passlock II light).

CovertCelery :

Your car may be "fixed", but how do you know which part was the problem if you changed everything out at the same time?

I wish I had the tools to debug this problem myself. Probably could figure it out very definitively in less than one day.

Just wanted to answer your question too real quick (even though I partially answered it in my above post...


The reason I know which part, or part(s) in my case, was the problem is that I went one by one. (The biggest problem sometimes is when you have multiple failures causing the problem, which in my case was)...


I did not replace "everything" all at once. I started with the BCM, because I was having issues with not just the PK2 light, but also "body" issues. That didn't do anything to fix my PK2 light, because the PK2 sensor in the ign. cylinder was testing as failed. (btw the car did not start at this point still) So the cylinder was switched out too... This time, the car actually started, but the PK2 light was still on. This meant there was something else still wrong. The aftermarket alarm system was taken out, and that cleared up all the problems.


Still security light free, nothing abnormal with the car as of yet.

Covertcelery:

OK, that all sounds reasonable to me. I thought maybe you had changed more than one thing out at a time.

How do you clean the cylinder? Do you spray it with WD-40 or actually disassemble and clean it by hand? I don't think I'll be doing the resistor bypass thing ever. I don't have much faith in that. I think it's the cylinder that is the problem in my car and that's what'll be replaced at some point, I guess (if cleaning doesn't work).

Covertcelery:

OK, that all sounds reasonable to me. I thought maybe you had changed more than one thing out at a time.

How do you clean the cylinder? Do you spray it with WD-40 or actually disassemble and clean it by hand? I don't think I'll be doing the resistor bypass thing ever. I don't have much faith in that. I think it's the cylinder that is the problem in my car and that's what'll be replaced at some point, I guess (if cleaning doesn't work).

Get some Electrical Contact cleaner, and spray it in there.

Just FYI to you guys about what to try to clean out your ignition cylinder... This was a helpful excerpt from one of the admins on AF.

Xeroinfinity sent me the following information:


One thing I will add about your troubles is its probly your ignition switch and or lock cylinder. I've replaced 1000's of these in GM autos over the last 7-8 years, its not just impalas and N bodies its ALL of them.

I think the problem is the cheap switch/cylinders crack and break or get dirty contacts inside them and cause the PK2 to trip the security light causing a no start or some other ill fated problem like dying randomly while driving :rolleyes: .

My 99 GA SE used to constanly have the security light on(but always started) when my wife drove it. I took all the unnecessary BS off her key chain, cleaned the switch with some elec. contact cleaner and blew it out, never have had a problem with it since and it has 200k miles on the stock switch/cylindr. :dunno:


BTW: I think he means "cylinder" whenever he was talking about "cleaning out the switch"...


Just a quick fyi to some of you that are going to try this... Get a small can of compressed air. You can find this at Wal-Mart or something (in the computer/electronics isle). It's like $2-$3 a small can... Radio Shack sells them, and a lot of other places do... Make sure and buy one with a little straw that you can blow the air through; this way you can actually put the little straw inside the cylinder and blow the crap out of it in a much more effective way IMHO.

Good luck.

-CC

I am attempting to do the resistor bypass for my 2001 Impala. I've taken enough dash off to get to the ignition switch bolts. I removed them but where do I go with the ignition switch from here? Earlier in this thread, a link on replacing the ignition switch seems to indicate to drop the switch down once the bolts are removed. It doesn't appear there is much room to work with to move the switch downward. Did I miss removing some other part of the dash that would make access to the switch easier? Do I need to remove the radio to get at it?

Thanks for the help.

Try looking under "Want to change out your radio" and "How to gain access to the back of your radio" here:http://impalahq.naioa.com/ Those might help you get it apart a little farther.

I have the dash apart enough to where I can access the radio screws. I have not taken off the center console, I'm not sure it would give me much more room to remove the switch, maybe just a few more access points to where the switch is currently located. After examining the switch more closely, I was able to access the PK2 wires and pull them out some between the steering wheel and where its normally bolted in. It seems like a tight squeeze to strip wires and solder, but I guess its doable. Is this how everyone else is getting to those wires, or are they able to back the switch out (wires and all) and work on it near the floor. The switch does not seem to move much as there are many wires which don't seem very flexible.

I have the dash apart enough to where I can access the radio screws. I have not taken off the center console, I'm not sure it would give me much more room to remove the switch, maybe just a few more access points to where the switch is currently located. After examining the switch more closely, I was able to access the PK2 wires and pull them out some between the steering wheel and where its normally bolted in. It seems like a tight squeeze to strip wires and solder, but I guess its doable. Is this how everyone else is getting to those wires, or are they able to back the switch out (wires and all) and work on it near the floor. The switch does not seem to move much as there are many wires which don't seem very flexible.

The best thing I can tell anyone to do, in case you feel like you don't have enough room to work with by pulling the radio out... You will prob. have to take off that silver looking knee guard underneath the steering wheel... Though to do this you will have to have a ratchet extension because the 4 bolts that hold it into the lower part of the console are a bit hard to get to; but nothing that can't be done.

This is the same thing that i had to do when I had to take out my alarm system and resolder the wires (as they are typically located in the main cluster of wires right underneath the steering wheel. Like I said - if you need more room, take that little silver cover off, its only like 4 bolts, and you'll have all the room you need.

I just did another bypass on a Malibu today for a customer. Took out the radio and grabbed the main power harness behind it. 20 minute fix.

I just did another bypass on a Malibu today for a customer. Took out the radio and grabbed the main power harness behind it. 20 minute fix.

It looks like I'm gonna have to try to attempt one for my buddy... But I think I'm gonna install one of those adjustable resistors so that I can fine tune the exact resistance it was reading...

I've noticed on some of the previous ones, the security light comes back after a while, well, its because it starting throwing a different resistance measurement... Its weird, but it was off by like 20 ohms... Then about a year later, another 50 ohms... So the Passlock system seems to be going bad - its giving off different ohms that it wasn't designed to send...

I had to change out the cylinder for the kid after the third time he cam back to get his bypass adjusted again because original readings by now were off by about 100-200 ohms....

Weird... Its seems like the older the passlock gets, the more resistance it throws on the wire... oh well.

I just want to know for the people that are coming to this thread... Especially now that its been stickied.

I know a lot of ppl are registered, but just view as guests - but if there is anyone registered.... I just welcome you to run on by and say hello in this thread and we want to know if anyone is in the process of possibly trying to fix their "security" light issues, but don't know where to go.... Well this is why this thread was stickied for you guys... Just between Poncho, Hemi, and me - we've been able to fix quiet a lot of people cars; and help them know what to do and how to do it.

If you guys have any questions, feel free to come into this thread and but some more opinions about this...


Also, what I'm really looking for is an AF user that has had these problems, and implemented the fixes in this forum, and got their car to work because of it...


I want to hear from you guys!


I also want to have a running tab on some of the mechanical problems having a bad BCM could cause.


Like in my cause, my airbag light went on and off intermittently... That's how mine started. The next year, the security light popped on once. Then, after a while... It wouldn't start intermittently due to the security light... Then ALL of my vehicles lights popped on intermittently. Fog lights flashing, interior lights flashing, etc... Then, nothing. Car never did start again after that. Stuck at a security light issue, with no crank... Not even a manual relearn would work...

Also, what I'm really looking for is an AF user that has had these problems, and implemented the fixes in this forum, and got their car to work because of it...

That's me...although my Passlock problem was on my Olds Alero, the system and the fix are the same. After installing the resistors, I have not had a problem in over a year. Here's a link to the procedure I used:http://www.automotiveforums.com/vbulletin/showthread.php?t=698861&highlight=passlock+bypass
This works on the Impala as well.
Here is an article that explains how Passlock works: http://motorage.search-autoparts.com/motorage/data/articlest andard/motorage/292005/169809/article.pdf
This will help in your troubleshooting, and help you understand what you are doing when you install resistors.

It looks like I'm gonna have to try to attempt one for my buddy... But I think I'm gonna install one of those adjustable resistors so that I can fine tune the exact resistance it was reading...

I've noticed on some of the previous ones, the security light comes back after a while, well, its because it starting throwing a different resistance measurement... Its weird, but it was off by like 20 ohms... Then about a year later, another 50 ohms... So the Passlock system seems to be going bad - its giving off different ohms that it wasn't designed to send...

I had to change out the cylinder for the kid after the third time he cam back to get his bypass adjusted again because original readings by now were off by about 100-200 ohms....

Weird... Its seems like the older the passlock gets, the more resistance it throws on the wire... oh well.

I have found that on All GM PASSLOCK AND VATS systems that it seems better to be just a touch higher in resistance value than to be dead on or a little low. Not sure why but that's what I've seen. Also, it doesn't hurt to run another jumper ground from chassis ground to the ground reference.

Just wanted to report that I have done nothing thus far to fix my SECURITY light problem (where the car won't start) and I will be getting through this calendar year with only the ONE incident where the car wouldn't start twice in a two-week window after driving 1000 (nearly continuous) one-way miles.

Also just took a shorter one-week 1100 mile trip without incident.

I'm still looking for the "smoking gun" here. I want to believe it's just the cylinder, but I don't know. Lastly, my car still has exhibited no other problems such as those weird BCM-related issues others have reported.

My Imp will start and run great even without the cluster installed...

Sidebar:

If you do take the cluster out and the vehicle runs........when you re-install the cluster the computer will need to re-learn the cluster as if it was new.

Will take 25-30 mins with the key OFF otherwise your speedo and gages will NOT work properly.

John

Sidebar:

If you do take the cluster out and the vehicle runs........when you re-install the cluster the computer will need to re-learn the cluster as if it was new.

Will take 25-30 mins with the key OFF otherwise your speedo and gages will NOT work properly.

John

Not sure if thats true on the impala, I've also run my car w/o the Cluster, and worked fine upon reinstalling.

Hi All,

After struggling with this problem concerning the Pass Key-2 synchronization, I'd like to pass on what I experienced.

I came across several methods for getting the new lock/cylinder to synch up with the BCM (Body Control module). In the end, believe it or not, none of these worked as prescribed on MY vehicle (2001 Impala LS).

But, what needs to be understood is the Security Light Flashing indication. You only get this by turning the ignition from Off all the way to Start, and letting it rest at On/ACC. For my car, any subsequent repeat step of turning the key back to Off, wait 5 seconds (or 30 seconds, or whatever), then turning to ON/ACC never produced a flashing Security Light Indicator.

That begs the question: What is the flashing Security Light Indicator? Answer: It is when you see the word "SECURITY" flash of and on three times in 3 seconds on the dashboard. On my car, this ONLY happened when I tried a complete Off to START key turn. I did not stop at ON/ACC. When I did turn Off, then turn to ON/ACC and stop, I did get what I thought was a flashing Security Light. Insted, this is simply an alternating status on the dashboard indicating there is a security issue (yellow Security indicator) and a battery drain indicator (RED BATTERY symbol).

Lastly, given my experience, I don't believe it takes 3 tries to get the synchronization done. But, if it does, so be it. The key is to wait long enough (usually at least 12 minutes) for the true Security Light flashing indicator to stop and the only thing shown is the battery drain red indicator. Then turn the ignition all the way off ( you can wait 5 seconds if you like, or thirty) then turn the key all the way and try and start the car. If the car starts, Whew! If not, repeat the steps until it does. If the Security Light never stops flashing, then something else is amiss. And it might just be the BCM. I wonder if the replacing of the BCM does an automatic synchronization which is why when there are problems that can't be resolved, the replacing of the BCM "magically" works!

Please don't knock the messenger. I was grateful for the posts that got me this far. The dealer was of no help!

H i new here ,, but had a probum in my S 10 [99] and used a formn to fix it it weas leaded gas wen it was 4 bucks a gl. melted the cat and would

Now down to brass tacks my old lady 2000 impla wont start not sure what is up with it .. I was fine then she let her sun who she thinks is ths best mac. in the whole word work on it ,, I told her not to let ANY ONE WORK ON ANY OF HER CARS BUT ME AFTER ALL HE IS THE BEST ,, he is just a parts swaper dont read any thing before he starts dosenot got a book just stars to take thinks apart real good with lown mowers but they dont have ECM PASSLOCK 2 etc any way he took the readater out along with one head light batt. weth out diaarming anything you should have seen it looked like CHOP SHOP has not beem right sence put my batt. in shout every thing off worked for a week or so ,, her batt started my car after it set for a week so that tells me somthing !! making a fool out of me and it is my fault becouse I told her bye it ,, the stuped little red light flashes all the time is that what you all are talking about

About any car my buddy dumped a cup of coffee in the concole of his new arccer {SP] legand now tranty wont work go in gear make any nose move burn jump so much for rice burners I have a70 RSSS that runs 9.90 on small bc so dont tell me chevys did not make good cars once in ther history

How do git back to default on this one
I have had 5 SSEi Bonny's and put up to 199,000 miles on them hard miles fryed a trany or two but the will fly I see they will run 160+ in the Silver State callange so I dont git it on this one I am GM all the way but thie is a bit to much ,, Got my old lady a new car it is a 65 Ford Galaxie XL conv. 390 CE code 330 hp matching number car and only paided 1500 for it and from the sound of things it will cost that much to fix the impala she gave it to me HELP ME !

We are still missing a lot of facts. The black plastic square with the 3 pin connector on the key cylinder housing. What exactly does it do for the car? How is it tested? Is it a proximity sensor? Is the passkey 2 sensor the piece of black plastic imbeded in the cylinder between the two copper strips? Can it be tested? if so how? It sounds like everyone is doing something that they don't really have the facts on and of course everything works since the problems are intermittant. My wife believes opening the trunk fixes it but you and I know better, right?

Does anyone have a test for the black box on the ignition case. It is a 3 pin connection to the ignition harness and has the numbers printed on it:
599096AA1
7122
Mexico
I am guessing that this is the location of my problem as it is no longer reading a correct resistance and telling the BCM to turn on the security light and refuse to start occasionally.

I found the link that promised a complete explanaiton of the passlock 2 system but when I tried it I just went to the auto parts web site that has no information.
Also I have a 2002 Impala and see no reason to pull the radio. Pull the lower panels unbolt that metal shield and drop the ignition switch down and over towards the steering column.

Here is the report on my 2002 Impala security light. I had 2 times when I had to wait for a restart after a trip to the store. The security light would come on while I was driving and I could guess what was coming next. I purchased the IB-PLJX bypass module and connected it as follows. The blue wire to the little yellow wire on the ignition switch harness. The black wire to the little black wire on the ignition switch harness. The red wire to the huge red wire on the big plug at the back of the ignition harness. There are 2 large red wires on the 2 plugs and both read hot all the time. I started the car and held the little button on the PLJX module until it blinked and the instructions say it has learned the bypass. I am putting the dash back together and will start driving the car again to see what happens. All the instructions I find everywhere are so pecular and not very helpful. Most say take out the radio but on my Impala there is no reason to go near the radio. I unbolted the switch and pushed it back and dropped it down so I had plenty of room to work. Of course I removed all the lower panel and the instrument upper dash panel. I will let you know how this works out. I had gotton a remote start a couple of xmass ago but I don't think I want to add it to the crazy chevy with all the bypass and expensive bcm etc why take a chance? I may put it on the dodge truck.

Just FYI to you guys about what to try to clean out your ignition cylinder... This was a helpful excerpt from one of the admins on AF.

Xeroinfinity sent me the following information:





BTW: I think he means "cylinder" whenever he was talking about "cleaning out the switch"...


Just a quick fyi to some of you that are going to try this... Get a small can of compressed air. You can find this at Wal-Mart or something (in the computer/electronics isle). It's like $2-$3 a small can... Radio Shack sells them, and a lot of other places do... Make sure and buy one with a little straw that you can blow the air through; this way you can actually put the little straw inside the cylinder and blow the crap out of it in a much more effective way IMHO.

Good luck.

-CC

Good day, I have a similar problem, along with a couple more, and thats on another post. But they all may be connected. I don't know. I have that problem, along with not being able to start on occasion. On 4 occasions I have not been able to start my car for some reason in the past 5 months or so. I boosted twice, and she started, Third time thought it was the battery, boost didn't work, new battery worked. Forth time, boost didn't work, played with wiring, and took out starter relay (crank) and tapped it on the inner fender, she started. Still got warning lights going off when driving...(tracton off, abs, security on occasion, parking brake, ), but everything seems to be operating ok. I appreciate any help youo can give me on this. Thank you for your time.

Just wanna throw one thing in if it was to get stickied (I don't know if its been said in this thread anywhere), don't suddenly think your ignition switch needs replacing. Try cleaning your ignition and try your spare key for a week or 2, as a worn key causes the message too.

I've had problems with getting key cut right, so i got sick of this one sided key (only works if a certain side of the key is pointed up.) so i switched to another key, and no PL2 message for bout a week now.

a good sign that your ignition might be going is: At night, the courtesy lights don't come on when you pull your key out or if you jiggle your key with your door open, and it stops dinging.

Good day Hemi, I have a '05 impala, and have been having some of the problems listed here. I have been using a key cut at WalMart since these problems started. The reason being is the "original " keys broke the plastic where they retain on the keyring. I have dashlight security lights randomly coming on (abs, trac con, pk brake, pass lock). On occasion, won't start, (4 times in as many months), turn the key, lights go out, like a dead short, old/new battery/ replaced battery, thought that was problem. As I have asked in a forum I have posted, need all help I can get please. Thank you for your time.

I have experienced this problem several times since I bought my used 2001 impala over a year ago. It had an aftermarker remote starter on it, which I had removed and the problem still returned after several months. I tried the wait 10 minutes to restart and leaving the key in the on position for 10 minutes before restarting. Both processes have had intermittent success. One day, when all elsed failed, I tried the same procedure that you can use to reset your change oil light on some GM cars. Take the key out and open the door so all power drops off. Then insert the key and turn it to the on position without starting the car. Fully depress the gas pedal three times, then step on the brake. I have only tried this twice, but it worked immediately both times. Not a perminent fix, but it has gotten me home.

I had this problem I luckily had a can of air in my car blew it into the ignition a big crumb flew out the car started it and i've never had the problem since(its been a year).

Or you can bypass it all together and have a car that starts every time. message me

Stupid Question, the Auto guy told me the BCM has to be in the car in order for it to be re-programmed? Is this true.

I replaced the Key/Ignition Switch a month ago, reprogrammed it and everything worked great. Went to start the car yesterday, totally failed didn't let me reset and now it will not start and get the 3 flashes of the security code again.

It's an 02 Impala LS with the 3.4?


HELP!

I'm going to assume this thread is necro exempt.
I have noticed something interesting with my failing PK2 system. It just happened to me now, but it has happened in the past as well. It failed to start, so I frustratedly tried a few more times and then gave up and waited the required half hour. I went at it again, and it failed again. Knowing for sure that I have another half hour to wait, I gave it one more angry, hail mary turn, and it started right up.

Does it not reset the timer every time you turn the key after the first failed attempt? Did I just not wait the full 30 mins, and that extra ten seconds was all it needed? Or did the key finally hit the right spot? Why did this happen?