Driver's side door lock security issue [Archive] - Forum


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02-12-2014, 12:58 PM
I'm still trying to sort out a security issue that is preventing a 2002 from starting. I think the driver's side door lock is messed up, and it's sending a signal to the Passlock system which is preventing the engine from cranking.

Has anyone encountered this before? Has anyone replaced the door lock before? If I do replace the door lock, do I need to replace the start switch to match the new key, how does that work?

Thanks. Any help at all would be greatly appreciated.


02-12-2014, 03:48 PM
The door lock has nothing to do with passlock. Is the light flashing on your dash?

02-13-2014, 02:31 PM
Okay, I've taken the door panel off and have taken a look around in there. Both the key and lock cylinder on the door are working fine. I see that the cylinder is connected to the door lock actuator via a rod. That is, when the cylinder turns, the rod goes down and door lock actuator is supposed to do its thing.

I'm fairly certain that the door lock actuator is broken. The actuator will not unlock the door. Question: Is the door lock actuator connected to the security system? (I think it is.)

The car will not turn over at all. The Security tell-tale does not flash. This is not a battery or starter issue, it's definitely a security issue.

Suggestions, input and help is much appreciated.



02-13-2014, 02:35 PM
Is the security light on at all? Like constant? Or flashing?

Flashing it wont start. Constant you can sometimes get the car to start.

The door locks are no where involved with the security passlock. Its all in the ignition solenoid in the dash.

Id try replacing that and see what happens. Either a jy one or if you have heavy pockets.. autozone charges 100 for them. Maybe you can find them new on ebay or rock auto a bit cheaper but ive never looked.

02-13-2014, 02:52 PM
Thanks Sleepyalero,

When I put the key into the starter switch and turn it to Start, all of the instrumentation and telltales in the dashboard light up and the RPM, speed, temp and fuel needles peg to the right, the fuel pump spools up, but the starter does not engage. When I release the key the instrumentation returns to zero. The "Security" telltale light does not illuminate during or after start attempts.

(When the car starts, it starts smartly. There is no starter drag or hesitation in ignition. It has a new battery. All wiring and connections look good. (The engine compartment looks pristine.))

The door locking mechanism on the drivers side door does not function properly AND the appearance of this problem coincides with the fail to crank issue. Both metal keys fit the driver side door, and they unlocked it initially, but now the keys will not unlock the door. Also, the locking button on the inside of the door is now only partially functional.


02-13-2014, 03:27 PM
Have you tried doing the relearn procedure? The BCM module wiring connectors or BMC circuit board could also be corroded which is very common on GA's and will cause various strange symptoms. The BCM module is located behind the access panel directly below the glove box. I agree with the others that the door lock system has nothing to do with the car not starting.

02-13-2014, 08:37 PM
The door lock is in no way shape or form connected to the passlock system. There isn't even a sensor on it.

The passlock system basically has four components, and it's only purpose is to keep someone from being able to easily start and drive your car by tampering with the ignition cylinder where the key goes, IE jamming something in there and breaking it and forcing it to rotate would not start the car.

You put the key in the lock cylinder and it sends a signal to the BCM, which in turn sends a coded signal to the PCM and if the code matches what the PCM has stored in memory it allows the engine to start and run. If there is a problem, the PCM disables the fuel system, not the starter. So since your car will sometimes start and run, but sometimes won't crank at all, I can tell you right now the problem is NOT with the passlock system. If it was, your security light would be on, and the engine would crank over but not start.

The fourth part of the system is the ignition switch, which is separate from but connected to the key cylinder. That's the part that actually activates the starter, so that's where I would look for a problem. The switch may be bad, or may have carbon build up from age and repeated use.

02-13-2014, 09:23 PM
This YouTube video seems to suggest that some GM door locking mechanisms are involved in the anti-theft system.

Does the video have any applicability to the 2002 Grand Am GT?



02-14-2014, 07:01 AM

Like I said, if it was a problem with the passlock anti-theft system, your "security" light in the gauge cluster would be on, and the car would crank but not start. If it's starts sometimes and other times doesn't even crank, it's most likely the ignition switch. Check that out.

04-10-2014, 06:57 PM
Please refer to this thread for a discussion on how to diagnose a starter/solenoid that dies with very little warning.