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Another GM Security Problem!!???HELP!!!!!!!

01-10-2016, 06:58 PM
Hello to all ,new to the site with a problem with my wifes 2001 Buick Lesabre !
She stopped at a local store(car running tip top as usual)turned off the car.As she came out of the store after about 20 mins. NO START! Security light is flashing all interior lights,radio etc work but NO headlights and if you turn signal it blinks real fast like a bulb out condition! The fuel pump does its prime up etc. NO CRANK,after say 15 seconds security light goes out,still NO CRANK!I did 10 minute reprogram(key in accy for 10-20 min) -no change!I also tried the valet key!NO GO!!!
I know GM had a few security problems but I have been out of the mechanic loop since loosing the use of my legs!Any help to point me in the right direction is much appreciated in advance! I can not stand so help me find the problem without crawling all over will be awesome!
Thanks Much!
2001 Buick Lesabre
6cyl automatic
155,000 miles
passkey 3 with transponder on outer ignition ring
battery is new and loads out fine

01-10-2016, 08:04 PM
Wife's Malibu had the same issue... The chip in the key is going bad and the car thinks its being stolen.

Turn the key to the run position and leave it sit (5-20 minutes) till the security light stops flashing. Then it will start and run fine.

Her did that intermittently for 2 years

Tech II
01-10-2016, 10:23 PM
I doubt it's the key since, his master and valet key, BOTH don't work.....

My first question is, have there been any accessories added to the vehicle like a remote start or security system?

Any work recently done to the steering column?

Vehicle needs to be scanned for codes with a scanner capable of reading P, B, and U codes......

01-10-2016, 10:31 PM
Both of our keys had the same issue, but it seemed like one was worse. Plus, once the thing gets set off it has to sit there to reset

01-10-2016, 10:31 PM
And mine never thru a code

01-11-2016, 06:37 AM
No mods to vehicle or steering colum,no remote starter!
Scanned with obd2 scanner got 3 codes
1-coolant temp sensor
2-low voltage current bank two ?
3-crank sensor- this code did not show 1st time scanned!!!

Thanks to all for replies and help !!!
Momma wants her wheels back !!

01-11-2016, 10:29 AM
# 3 a bad crank sensor will cause your problems. One on our Regal went years ago...result No start.

#1 coolant temp. Car could run hot or cold. Thermostat or sensor probably bad. Thermostat easiest and cheapest to replace. Do first before replacing the sensor. Remote start will not work (said you didn't have a remote)

#2 probably the oxygen sensor. Bad unit, or bad connection to sensor.

01-11-2016, 12:11 PM
Going from accy to start there is nothing but the sound of wind in the trees!Its not just a NO START its a NO CRANK OVER condition!All dash lights go out and come back when returning key to accy!

01-11-2016, 02:24 PM
The fact that the dash lights go out in START suggests to me a possible starter issue. START essentially shorts the battery through the starter motor. This should be momentary as back EMF will reduce this current as the starter spins up. But if no spin, then no back EMF and no reduction in current. The starter solenoid should also engage, but a short through the starter motor may inhibit this as well.

Measure battery voltage when in START. If it drops well below 13V, then check out the starter.

Good luck.

01-11-2016, 03:10 PM
Going from accy to start there is nothing but the sound of wind in the trees!Its not just a NO START its a NO CRANK OVER condition!All dash lights go out and come back when returning key to accy!

Sorry, that is what I meant...no crank. Nothing but dash light do go out. I would get the crank position sensor checked first, and if that is not it, then check the starter system and motor.

01-11-2016, 04:23 PM
Wouldn't a bad crank sensor cause a "no start" but not a "no crank"?

How does a bad crank sensor explain losing the dash (and other?) lights when in start?

It may be a bad CKP sensor, but how it would cause the symptoms is not clear to me.

I would check the starter first since it is probably easier (or cheaper) than checking the CKP sensor.

Good luck.

01-11-2016, 04:48 PM
when I used my boys obd2 I only got coolant sensor code!
Over the holidays I was extremely sick with the flu,Momma wanting her car back,local hero ran his obd2 and came up with crank sensor and replaced without my prior knowledge ,of course it didn't work but he sent me a bill for 200. and also tried installing a new bcm used from ebay ( the no headlight issue)!! My first thoughts was the starter as well, he also benched it and said it was fine,so he says ! Remember I sometimes get tons of unwanted and unasked for help because I can not walk ! People forget my legs do not work but my brain and reasoning still do !!
Thanks to all! The starter is another $115. so I better check it right !!
Thanks again!

01-11-2016, 05:33 PM
Wouldn't a bad crank sensor cause a "no start" but not a "no crank"?

Well it was eight years or more ago, and I seem to remember the car wouldn't even crank. I could be wrong.

Tech II
01-11-2016, 10:11 PM
I agree.....

A bad crank sensor will not prevent a car from cranking.....

Are you the original owner?

Reason I ask is I have seen remote start systems poorly wired into PassKey III systems causing a no start, somewhere down the road....

Regular scan tools/code readers can only read "P" codes, they can't read "B" and "U" codes......

If the SECURITY light is flashing, you have a PassKey III problem.....

Also, your reprogram procedure is incorrect, as well......

Also you say your headlights do not work? Manually or automatically?

As you can see, the PCM grounds the starter enable relay to crank the vehicle....however, if the PCM doesn't receive a signal via the Class II circuit from the Theft Deterrent Module, it's not going to ground the relay, or fire the injectors...the module is sending a signal to the IP cluster, showing there is a problem, because the SECURITY light flashes....

The reason why I asked if there was any steering column work done, is because I remember a TSB about the exciter ring not being in the correct position around the lock cylinder...



01-12-2016, 11:17 PM
Tech 2
Thanks personally !!
Unfortunately I can not read schematic, its extremely unfocused and I can not get computer to save as !!
You sir are the only one speaking TECH knowledge!
I am owner #1 never 1 problem in 15 years-thank you GM
Nothing has ever been added to Mommas wheels!!
Never 1 problem -NEVER ONE !! Maybe she has been super lucky !!

Get in!
Turn ignition to accy.
All lights come on (security flashes very fast) fuel pump primes-all including security light goes off after a few seconds !
Turn Ign. to crank- ALL LIGHTS , I mean ALL go OUT !!! NO CRANK !! SILENCE !!
Back to accy all come back with a fast flash security!Goes out after a few !
All forward lights -ie head lights, turn ,park etc not lit! Either l or r turnsignal makes a fast blink like a bulb out !
I have only had use of a obd2 and were I live is @ 3 hours from the nearest GM dealer ! Thread says Tulsa but I actually live in the Winding Stair Mountains over 3 hrs away to east-3 hrs west of Little Rock !
Thanks again !!

01-12-2016, 11:34 PM
Tech II
Can I get around the pass key 3 ? There must be a way, I personally DO NOT want the option!!! I am not worried about theft of an $1800. car. I am worried about my woman getting from a to b with no problems !!
I live in the sticks and would like GM to give me the option of having this Pass key security option/ problem or not ! It would be nice if I had the ability to turn on /off like the airbag etc!!

01-12-2016, 11:38 PM
Does a passkey 3 problem explain losing all lights when turned to start?

01-12-2016, 11:39 PM
I also forgot ,
Tech II ,What did I do wrong with my reprogram method I received from you tube !??
I know , believe 50 % of what you see on you tube and forget the other 50 %
Please Yall don't get p/o its a joke albeit a bad one !!

01-13-2016, 07:08 AM
TechII is far more knowledgeable than I, however, I have rebuilt a few engines and carbs in my time. LOL. I wanted to lean about this Passkey and so I did some searching. Found some things that may or may not help. This link sell a product to bypass the security system.

you have probably tried reprogramming. Here is a link on how to.

This looks interesting.

I don't know how inclined you are to disable it yourself however here is a proceedure.

All kinds of info out on the net. Good luck.

01-13-2016, 10:08 AM
Have you tried turning the key to the on position till security light stops blinking and the starting the car without clicking back to the off position? If its truly a passkey problem and not something else then the car should start. It may take up to 20 minutes for the security light to stop flashing.

There are ways to bypass the passkey. Putting a resister that matches your key inline is one way. Adding a remote start is another. Both are pretty cheap options

Tech II
01-13-2016, 01:05 PM
Ok, What happens to the SECURITY LIGHT, when you turn the key to the "on" position(not the crank position)? With the key in the "on" position, all your dash lights should come on, and the SECURITY light should come on solid(should not flash), and then go out in three seconds....the only thing that should flash(7x's) is your SIR(air bag light).....

Now turn the key to the crank position.......in the crank position, your idiot lights will go out.....do you hear a click at all from the starter?

So, if you turn the key to the "on" position(not accessory), and the SECURITY LIGHT flashes, you have a PassKey III problem......if it comes on for three seconds, doesn't flash, and then goes out, there is no SECURITY problem.....

Then you have to check for power at the starter with the key in the crank position, at the "S" terminal(purple wire)....if you have power, then you need a starter.....if no power, try starting the car in neutral.......if still no power, then you have to check the starter enable relay circuit.......If you ground the relay, the car should crank......

Tech II
01-13-2016, 01:52 PM
There is some confusion here......

There is PassKey I, II, III and PassLock.....

With all three PassKey systems, when you turn the key to "on", after 3 seconds the SECURITY/THEFT light will go out......with PassLock, when you turn the key to "on", it stays on....it doesn't go out until the car starts......

What is common to all systems, is, if the light flashes, you have a security problem....

I and II, uses a resistor in the key....III uses a transponder.....PassLock uses nothing, it's a blank key.......

There is no reprogramming for I and II....there is for III....it's a 30 minute procedure, so if you have a weak battery, or are trying to do it in winter, you should have a battery jump box attached to the vehicle, and make sure your auto headlights are not on.....Polarzak gives the correct procedure in his second link....can only do this with a master key, not a valet key.....this procedure is only used when you lose your master keys.....

Passlock has different procedures....the early years, were a thirty minute procedure like Passkey......the later years, was just a 10 minute procedure.......

As far as bypassing Passkey is concerned, I and II are easy....it just involved inserting a resistor, of the same value, as your ignition key....PassKey III is more involved.......you would need to remove the transponder from the key and insert it into a special module, and then wire the module into the vehicle....

01-17-2016, 01:32 AM
Hello ,and a huge thank you to all that have tried to help me with my MRS. Buick NO GO !
As of today I towed it home from the local HERO repair shop, notice I said towed it home! Hero took my plate and was gonna call the Police cause I didn't want to pay the 180. for him to tear my wifes car apart and not fix it!!
All the headlight /twilight switch is broken ,same with steering wheel enclosure,kick board , dash trim, pass side kick plate,bcm is all hanging out or removed all is thrown around inside willy nilly !!I will get pics!!

ANYWAY, my friend helped me tow it back to MY HOUSE/SHOP !!

AS her car stands,back from Hero shop !!26 DAYS LATER ! NO, NO chat from the hero mech !!
ME and the Wife --$193.50 YES THATS MINUS ! I Had to pay or have a talk with the POLICE before I could haul Momma's rig to home/house !

Car sitting ! Security flashes fast !NO TOUCH
Turn to accy- all dash lights come on ----security goes off after 5 seconds!
let off to accy same as first time ZIP !!
BCM,Crank shaft sensor changed,more wires than I can count --wire ,all dash wires,ignitition,passkey 3,----@12 wire

coatings skinned of coating under dash,all stuff I did not do !

I guess I will start by myself fuse by fuse wire by wire etc!!
Is there a park/neutral switch or transaxel type?
I just have to go one by one!
Thanks so much to yall !!

Sorry not meant to offend, just me, straight up old fart to the point !!

01-17-2016, 02:25 AM
Sorry to all !
I am having a hard time with posting etc ! I thank you all @tech11 you are smarter then I and I thank you as well,I don't know if this working or not , not to computer savy,but not stupid! An old aircraft mechanic that's trying to keep his cars going !!
Thanks for your help !!

01-17-2016, 02:38 AM
Yes its a pass key 3 !!
Delco #16266469
Version 0.1000

01-17-2016, 02:40 AM
I am so sorry guys! I can't walk, type or mechanic either ! I hope you understand !!!

Tech II
01-18-2016, 09:45 AM
So, this mechanic basically, tore your car apart trying to fix the problem, and left it that way because you refused to pay him? Did he say, he had no idea what the problem was?

Hate to say it, but you might have to have it towed to your local GM dealer(does not have to be a Buick one), to have this taken car of.....

Once again, I have to ask...you insert key, and rotate it clockwise to the "on" position(one stop before the crank position).......What does the SECURITY light do? Flash, stay on, or go out after 3-5 seconds?

01-18-2016, 04:06 PM
Yes he tore it apart trying to fix it,added a crank sensor,and a used bcm!
I had not heard from him since before new years - Finally got his wife to answer phone she said his partner fell and broke his hip so he had to take a job elsewhere while his partner heals!

I got PO,d that he didn't do anything in 3 weeks time( not even a call)but tare apart the dash and leave it that way!so yesterday-Sat. my buddy helped me go get it with a trailer,
hero mechanic would not let me move my wifes car(had it blocked) until I paid him the $180 for practicing on her car! parts and labor!!

At least now I have it home,so I can look things over myself!I am gonna take pics of his mess and send him a bill when its all back together!

AS it sits here at home
-Security light is flashing! Get in shut the door--Flashing fast! Insert key go to ON-light flashes for @3-5 seconds gos off !!Go to crank all lights go out!!
Relax key from crank position to ON security light comes back on flashing and stays on 3-5 then off again !!

Before when it first stopped running security flashed fast and never went out but pump would cycle and lights worked!! Now-No fuel pump cycle no headlights-auto or manuel on !!

I did try shifting to neautral and back to start -no crank !! I wasn't sure if it has a tranxle switch or not!

I did just now come back from autozone with a Haynes w/schematics !

Yes I thought of takeing to gm but there isn't any within hours all directions !!
thanks again to all !!

Tech II
01-18-2016, 09:42 PM
I am afraid that "used" BCM could be your problem.....do you have your old one?

01-18-2016, 11:10 PM
Yes,I replaced the bcm with the original, No changes !I read earlier this evening that the bcm should be reprogrammed before installing !!
I ran out of daylight and the battery needed a charge! I am going to start with rear fuse block and work my way forward on each fuse in am if it does'nt freeze rain/snow!
Thanks again for all your input!

Tech II
01-19-2016, 11:20 PM
No, the original would not have to be reprogrammed.....the one that replaced it, could have been programmed wrong or was the wrong BCM....

01-26-2016, 08:43 PM
Can a BCM be reprogrammed outside the vehicle?
Can I send it to someone to be programmed or does it have to be with the vehicle?
So far no bad fuses found -rear fuse panel!
Its been slow going because of weather and not having help !

Tech II
01-27-2016, 04:36 PM
I don't believe a BCM can be programmed outside the vehicle.....

Like many modules in GM, one module with a specific part number, can be used in different cars,,,,that's why it has to be in the car to be programmed for the specific car.....and depending on the year, you can't just swap modules, because in the newer vehicles, the module has to have the car's VIN number in it.....if you try to swap one out of another car, even with the same year, model, and options, that module will not work in another car....

Are you just trying to shotgun parts on this, or do you have access to something like a GM Tech II scan tool.....

01-30-2016, 06:09 PM
I do not have any way to a tech 2 !
I am trying not to shotgun parts on it, I am not rich enough to have it moved to a dealer 3 hours away,and have not found a local tech 2 mechanic either!
I asked about sending out a bcm for programming only as a for thought that if that's what it turned out to be,I would be prepared to send it out !
As of today!
I have no power in the front fuse box to the fuses that run fuel injectors ,sir!? and Ignition 1 and 2 fuses !
Horn and headlights still inop but fuses have power! Horn relay does click!
That's as far as I got before my back gave out !
If I am being a pest say so ,I will no longer write !

Tech II
01-30-2016, 11:05 PM
Well, you are kind of between a rock and hard place.....

One of the first things you have to do is check for codes......you also have to see if you can communicate with various modules in the car.....to do this, you need a scan tool like a Tech II.....loss of communication with a module happens 4 ways.....loss of power....loss of ground.....open/short in data line.....bad moduel....

You also need schematics to trace power concerns.....could be something as simple as an open wire or a bad ground....if a visual inspection shows nothing, then tracing schematics is a must......

Blue Bowtie
01-31-2016, 10:25 AM
It may help to split the system down the middle and determine a direction to investigate. Does the IGN1 relay energize with the key in the RUN/START positions?

If NOT, can you jumper the 87 and 30 contacts and make it start?

Has anyone checked the voltages into and out of the ignition switch?

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