Questions and Answers
Deville Security Light
Q. Vincent, I have a 1990 Cadillac Deville, 4.5 engine, ABS brakes, front wheel drive and 126,000 miles. The problem is I am receiving a security light on the info system and the car will not start at all. It was running fine. I have removed the negative cable from the battery several times in hopes it would reset the computer but to no avail.
I am getting a code F11 but none of my manuals tell me what an F11 is. Could you tell me how to reset the security system or clear this code? Need help badly.
Randy
A. Code F11 indicates a fault in the "A/C High Side Temperature Sensor Circuit". What that has to do with the car not starting is beyond me. But it is a General Motors product so anything is possible.
The missing clue is whether the engine cranks and doesn't start or the engine doesn't crank at all.
The security system on your car has to be checked with a special tool called an "interrogator". This checks the security system functions and helps pinpoint any problems. If the engine doesn't crank at all, then the most likely cause would be the ignition lock or keys. There is a pair of small contacts that check the chip on the key. If the contacts loosens up or break, the car will think someone is trying to steal it and shut down.
Additional Information provided courtesy of ALLDATA
