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

[skynut831]

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

[paulfromoh]

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]

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......

[paulfromoh]

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

[paulfromoh]

And mine never thru a code

[skynut831]

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 !!

[polarzak]

# 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.

[skynut831]

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!
thanks

[DrRadar]

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.

[polarzak]

Originally Posted by skynut831

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!
thanks

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.

[DrRadar]

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.

[skynut831]

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!

[polarzak]

Originally Posted by DrRadar

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]

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...

[skynut831]

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 !!