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Passlock light keeps coming on steady

I have a 2008 GMC Sierra. It starts just fine and runs just fine. The ONLY issue I have is that the Passlock/security light on the dashboard will come on shortly after starting the vehicle and stay on until I turn it off. Is there a fuse or relay or something that could be causing this?

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If the light comes on after you start it than there is a problem with the Passlock system. You will need to pull trouble codes to find out what is going on. You will need a high end scan tool to do this. The good news is Passlock system is somewhat disabled when the light is on and there shouldn't be any issues getting the engine to start. The bad news is if the battery goes dead or it is disconnected the vehicle will likely no longer start. So its a good idea to get this resolved as soon as possible.

Posted on Jul 31, 2013


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Posted on Jan 02, 2017

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SOURCE: the vehicle starts , but immediately dies.

I would look at the tach wire it is probly not getting signel back to the remote starter usaly a purple wire on remote starters

Posted on Mar 02, 2009

  • 1 Answer

SOURCE: Passlock II issues for 99 Tahoe

turn key to start position for 10 minutes and it will reset passlock

Or, once you're tired of being stranded for 10 min every 6 weeks or so, try the following:

Here's the "fix" I did for my 99 tahoe. Took the cover off the steering column, unplugged the sensor from the cylinder *while* the car was running. it's a 3 wire plug red w/ white, orange w/black and yellow. From then on, the car will always start and ignore the sensor. The only negative is the security light stays on. Replacing the BCM only postpones it from happening again if the problem is the resistance in the ignition lock cylinder. Check out the following links. Good luck.

Posted on Mar 18, 2009

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SOURCE: check engine,airbag and wrench lights come on the dashboard

Sound like they tapped into a low voltage ingnition wire or a data bus wire. It needs to be doubled checked for correct wiring. These new cars are very sensitive computer systems, its more than likely an improper wire.

Posted on Jun 04, 2009

  • 1 Answer

SOURCE: My 2006 Mazda 3 occasionally will not start.

i was told by my rep @ mazda that there may be corrosion on the power wire connected to the starter and it should be checked and cleaned

Posted on Dec 16, 2009

  • 355 Answers

SOURCE: security light stays on and somtimes it will turn

The security system (VATS/PassKey) is having problems, it's typical on those cars. You can find a great write-up here: , it was the only thing that saved my Park Avenue.

Posted on Sep 10, 2010

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