Cadillac Repair: cadillac repair, minuits, componant

Question
my'92sedandeville 4.9motor ses&svs&oil&coolant&sa/clights goon then blink off on fuel&climategauges aletterc orhalf2 stay on for fewminutes with air on byitself same lights blink on go off then all gauges are back to normal  
don't know what's going on milage 92,800

Answer
Hi Tina,

     You sure have alot going on. And there could be more than 1 defective part causing this problem to happen.

     That said and since both panels display a "C" one of the panels could be starting to go bad, the programmer for the a/c or a faulty BCM/body computor module are the likely suspects. The bad thing is that until the panels display the "C" long enough...like 30 minuits or more...for you to disconnect everything one at a time there really isn't a good guess what to replace. There was a service bulletin out that said that the panels might be manufactured wrong and missing a capacitor but those should have been found and replaced by '96.

      So what is happening is that all those parts are connected by a data or 800 line. When a componant on that line starts to short out it confuses the computors and the "C" or "D" will display. Kind of like if 5 people in a room were talking and then all of a sudden one of the people started to speak spanish. The other 4 people would be confused because they don't know the language and instead of "C" they might say huh or what?

     If there was some work done on the car recently and then this problem started to happen then rechecking that area should find the problem. Otherwise you will just need to wait until the "C" is on longer and then the bad part should be easier to find. Bill