1998 GMC C3500 Security light

1998 GMC C3500
165,000 MILES • V8 • 2WD • AUTOMATIC
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3500 GMC
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Vehicle will crank over but will not start. Security light keeps coming on. Not able to get a diagnostic reading from it.
May 6, 2008 at 9:32 PM
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PEAR69
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Your vehical has a security system called Passlock. It relies on a resistor value to activate the ignition system. the resistor is probably going bad, but you must take it to a dealer to fix this..However, you can temporarily bypass this and start the engine by doing the following---
1--turn the key on but do not crank the engine
2--the security light is on or blinking
3--wait until the light goes out or stops blinking, this takes about 10 minutes.
4--now, turn the key off
5--within 3 seconds turn the key and start the engine.
This will bypass the passlock system for a while, but to fix the problem you must see a dealer.
May 7, 2008 at 5:02 AM