Cadillac Repair/caddilac


QUESTION: Just replaced my 1986 Caddilac Sedan DeVille with a new battery and now the digital gas gauge, digital air conditioner, and stereo won't light up or work what can be the problem

ANSWER: Hello,

Did the stereo work before you replaced the gas gauge and a/c control?

There are two power wires to the factory stereo. One is constant power for station pre-set and clock memory. The other power wire is switched so the ignition is in on or acc. You could have a bad fuse or two and the first thing I would check would be the fuses. Otherwise, when you changed the a/c control, you disconnected power going to the stereo.

---------- FOLLOW-UP ----------

QUESTION: Nothing was done to anything but a new battery and before the battery was replced evrything was working just fine the mechanic said there was a pinched wire which he replaced and a new battery.


OK, and the pinched wire was for what circuit? All you can do is check the radio fuse. If that is good, then stereo has to be removed and has to be checked to see if power is going to it. If power is going to the back of the stereo, and the stereo doesn't work, stereo is no good. It's just that simple.

Cadillac Repair

All Answers

Answers by Expert:

Ask Experts


Rob Painter


Alarm system questions cannot be answered on this forum. These systems are not what I can answer. Without being physically at the vehicle and not knowing what kind of electrical service has been done on the vehicle, there is no possible way to give an accurate answer over the internet. My expertise is in Ignition/key based anti-theft systems. These issues include GM VATS (resistor chip in key blade) PASSLOCK (MRD)-ignition lock rotation based, no special ignition key and the PKIII Transponder (computer chip in key) systems. These systems are not alarm based and are integral with the starting of the engine. This is why I cannot diagnose alarm problems without physically looking at the vehicle: Alarm systems are a completely different annimal than ignition key/lock based anti-theft system. Many alarm questions come from vehicles 10 years old, and since older, many hands that had been involved over the years.I am an expert in all GM factory (ignition/key based)systems. Alarm system questions pose to many situations beyond my knowledge as to what has been done to the vehicle over the years. Some guy may have actually wired the stereo into the alarm system. Who knows? Over my past 30 years in vehicle wiring repair, I have seen unbelievable wiring disaters done by guys that consider themselves "mechanics." I have seen stereos and alarms intalled using surgical tape. I have seen modules burn up, un-fused circuits, wiring jambed between the doors and even lamp cord used for a starter kill. To answer alarm questions over the internet without examining the vehicle is like asking; What does it take to remove a dent?


Education/Credentials-ASE certified. 11 years with a GM dealer and 17 years with a repair facility dealing with only the repair of theft recovered vehicles.

©2017 All rights reserved.