Fairly new and starts just fine if it's not below 30 or so. The battery is new.
New Cavalier starting problems
- Thread starter 97prizm
- Start date
This is a really basic system that only detects if there is a key in the lock cylinder or not, it's just enough to keep the Kia Boyz away. Inserting a key, any key completes the circuit and let's the cluster know if it's okay to allow the vehicle to run. There's no resistor like earlier systems and no transponder like modern systems. It can only be the cluster, lock cylinder or wiring.
The parts in the cylinder are designed to break if someone tries a Kia-style theft of "punching" out the cylinder, or otherwise forcing it without the proper key. It's not exactly looking if a key is inserted, but rather if someone tried to force it to rotate without the tumblers aligned as they would be with the matching key inserted.
Apparently the hair dryer trick worked this morning in the 14F cold. After heating the lock mechanism with a hair dryer for a few minutes it fired right up.
The only caveat is that the ignition tumbler has a hall effect sensor built in. It's known to go bad. This morning my dad and heated the lock mechanism and after a few minutes it fired right up.
I've replaced the lock assembly but it won't seem to relearn. The anti theft light is supposed to flash then go out after 10 minutes but doesn't. This is supposed to be a straight forward repair. Any thoughts?
I had that happen to my old suburban with passlock 2 once when the battery shorted. My mechanic told me to do the relearn and gave me the directions and if it didn't work then to let it sit without power for an hour and do it again but it worked without needing to disconnect and wait. But if something wasn't wired right or the hall effect sensor doesn't work it could be a bad cylinder as new parts aren't great these days. There are different relearns so maybe look through this.
The lock cylinder magnet sends a resistance signal through the yellow wire to the bcm so that's why the resistor trick works. If you haven't tried that i would, do that and do the relearn again and it should work.
https://www.cardone.com/content/Products/PT77-0011.pdf
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It's been a while, but I recall cutting the yellow wire while it's running cripples Passlock's ability to interfere with your car running.
Please remember that Passlock and Passkey are two different systems; Passkey is "better" and has the resistor chips in the keys. Passlock is GM ripping off their own intellectual property to sell a cheaper system.
Please remember that Passlock and Passkey are two different systems; Passkey is "better" and has the resistor chips in the keys. Passlock is GM ripping off their own intellectual property to sell a cheaper system.
There shouldn't be a relearn. You might have a bad lock cylinder.
According to a few GM forums there are as many as 15 different resistor values. Several articles more or less say there's always a relearn process. The non-blinking anti theft light is what's throwing me. A bad part is possible, but I've come across two posts online that says it may need a professional mechanic to sync the vehicle. Quite frustrating.
How do I test the cylinder resistance? Unplug the harness and put leads across them?
If the engine starts then stalls but the key light is either off or on steady (i.e. does not blink like it would for a faulty key cylinder) that probably means the cluster part is bad.
There are B codes from the PCM that would confirm no link with the cluster.
There are B codes from the PCM that would confirm no link with the cluster.
So the hall effect sensor was bad. It wasn't correctly crimped to the tumbler.
If you look at the black plastic piece it would pop out when you turned the cylinder. This is why the theft light wouldn't go out. My dad and I found a repair where you start the car and unplug the cable then turn off. It causes the theft light to stay on but bypasses the anti-theft.
Funny you say that as there are two black and one white wire on the harness, no yellow.
Figured it was a bad cylinder. The 15 different resistances are for the original system that had the resistors built into the key blade. Your key doesn't have the resistor.
