Passkey security ignition cylinder removed showing where common broken wires are.
1- Wires for security sensor break here
2- Connector under dr. side lower dash panel to
test resistance of sensor with key in ignition.
Open circuit means wires are probably broken,
and replacement of ignition cylinder is needed.

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GM passkey security system.
Common cause for car to not start.
Theft / security light on dash.
WARNING LIGHTS
Theft / Security Light

The security system on todays cars and trucks prevents the vehicle from being stolen. There are many
variations of the system going back to the early 1990's.
This warning could be on when the engine is running, indicating a fault has been detected in the system. If left
unrepaired, there is a good possibility that the car will eventually not start.
There are several different possibilities for the cause of the warning, depending on the make / model / year of
the vehicle. Anything from a bad ignition cylinder wire, to a bad cylinder to a dad Body Control Module (BCM).
After market (non-factory) alarm and remote start systems can cause havoc with the factory theft system,
causing this warning light, or a no start.
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11-5-10
ignition wont turn to off position and wont release key.
Comments
This could be a badly worn or bent key, a binding
cylinder, or a shifter problem, depending on what type of
vehicle this is.
3-1-11
2001 s-10 key is out of ignition truck is still running cant turn truck off
If the key is ion the OFF position, then it sounds like the
ignition switch is bad. If it wont go all the way to the OFF
position and the key comes out, the cylinder is bad.
7-4-11
just had my ignition replace because the car was stolen but don't know if they replace the
cylinder try doing the 10-12 minute step n it still wont start but theft light is still on
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7-17-11
igot home killed the engine and 3hours later tried to start the engine and the starter didnt engage
7-17-11
igot home killed the engine and 3hours later tried to start the engine and the starter didnt engage
7-20-11
OK. Going o need more information than that. What kind of car or truck? Is the battery tested as
good? Any warning lights on the dash?