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Q: security system wont shut off and vehicle wont start has no electrical power at all

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security system activated and vehicle wont start got the vehicle 6 years ago had no problem with security cant find fob

My car has 140000 miles.
My car has an automatic transmission.

A: When security systems fail, you can reset i...

When security systems fail, you can reset it on most vehicles by unlocking and locking the drivers or passenger doors two or three times in a row. One other trick is to disconnect the battery, turn the key into the run position and reconnecting the battery. If either of these don’t work, then you probably have a failure in the system.

A common failure that leads to security issues are the door switches. The driver door being the most used is more often than not the culprit. Door switches indicate to the alarm system that the doors are closed. If the door switch is in a position it doesn’t expect, it will assume someone is attempting to steal the car. Checking the door switches can be done easily by turning on the key, opening each door individually and watching the door ajar light to see if opening the door turns the light on. Of course, if the light is on with all the doors shut, you know there is a problem.

Another common failure on GM vehicles is the theftlock wiring breaking. These wires are part of the sensor that is activated when the key is inserted into the ignition. You can test this by turning the key on for ten to fifteen minutes, then starting it. If it starts, you have a theftlock problem. This will require replacing the ignition lock cylinder.

Good luck! I hope this helps you out.

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