2010 gmc won't start

Colin Stickland

• 22516 Answers
• Posted on May 02, 2011

SOURCE: 1998 GMC Sierra won start security

try the spare key and if that doesnt work then call breakdown truck and have taken to dealer

Joe Taylor

• 2229 Answers
• Posted on Mar 27, 2012

SOURCE: my security light stays on & won't let my 99 gmc 6.5 diesel sierra start any solutions

Yes, the system is called Passlock, and malfunctions regularly. Go to this link for an explanation of how it works, plus some tricks and tips on how to reset it, or bypass it.

http://vatspasslockpasskeysecurityhelp.yolasite.com/

Joe Taylor

• 2229 Answers
• Posted on Sep 25, 2012

SOURCE: 2002 gmc sierra won't start, security light came on

The security light is a visual indication that something in the car's antitheft system is failing. In most GM cars and trucks there is a hidden system that most people are unaware even exists. From the moment you put your key in the ignition, there begins a constant line of communication between your key's security chip or transponder, to the ignition's lock cylinder, and then to the car's TDM (Theft Deterrent Module). These 3 parts are in CONSTANT communication. If the key is in the ignition, then these parts are sending signals to each other. The security light illuminates when that signal gets broken, even just for a second. When the signal breaks, the car misinterperates this as an attempt at theft and goes into antitheft mode. The car thinks its being stolen or hotwired because it is not getting that signal from YOUR specific key. This is why the security light turns on and shuts down your vehicle. Remember too, the TDM controls the security light. Sometimes you can have ALL the symptoms and no lights.
This link may help you.
http://vatspasslockpasskeysecurityhelp.yolasite.com/

Joe Taylor

• 2229 Answers
• Posted on Mar 24, 2014

SOURCE: how do i reset 2010 GMC Yukon XL security system

30 MINUTE RELEARN PROCEDURE

1. Turn ON the ignition, with the engine OFF.
2. Attempt to start the engine, then release the key to ON, vehicle will not start.
3. Observe the SECURITY telltale. After approximately 10 minutes, the telltale will turn OFF.
4. Turn OFF the ignition, and wait 5 seconds.
5. Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes. The vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.
6. Important: The vehicle learns the password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
7. Start the engine. The vehicle has now learned the password.