Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
Hello, Eddie here and I will do my best to help. You probably blew a fuse out in the main power fuse box under the hood. Do you have a 12 volt test light or volt meter by chance? and can you check the fuses out in the main fuse box under the hood? touch the blade tips of the fuse with the test light or volt meter, and it should light up on both blade tips you don't have to pull the fuse all the way out to check it, that is the easiest way, the larger amperage fuses, you can look through the clear plastic window on the top and visibly tell if they are blown. Check that out and let me know what you see there.
Alright, Thank you.
Alright, I follow you, You checked all the fuses out under the hood as well correct?
Alright, Let me know what you find there. Thank you.
Alright, If all the fuses appear good, then the next thing I would do, disconnect the battery again, Leave the negative cable off for about 30 minutes, then reinstall it and see if you regain any function. If that doesn't work, then I would get a shop with an advanced type scanner, or if you can obtain one somewhere, Read off any trouble codes in all the modules, and clear out all the codes, and see if that helps, I would think the navigation system and the body control module would store one or more codes for the problem your having. If clearing out all the codes doesn't help, then it's very possible you cooked some diodes in the instrument cluster for that oil gauge, or in the navigation screen. Diodes are one way check valves basically that let current flow one way but not the other, and when a battery is hooked up backwards, it can damage those diodes on the printed circuit board. I hope that isn't the case, but that is worst case scenario. Let me know if you have any further questions. Thank you.