Cadillac Repair: 1989 Cadillac Seville, cadillac seville, fuel gauge

Question
--I am incorrect in stating it is a seville it is a deville.  Do you have any ideas?

Thanks, Tim-----------------------
Followup To
Question -
The automatic temperature controller and the Fuel gauge display the letter "C" when the car is started and the temperature controller is acting up.  Do you have any suggestions for testing or repair?

Thanks,

Tim
Answer -
Hi Tim, I've never seen a Seville do that. Are you sure its a Seville or did you mean Deville? Bill

Answer
Hi Tim, First disconnect the programmer connector. If panels return to normal then replace the programmer. If still c then disconnect the climate panel...if ok replace it, if still c on the fuel then plug in the climate and unplug the fuel. If ok replace the fuel if still c then check for shorts to ground in ct713 which is a yellow wire that hooks up to all panels. If ok then check the BCM connector or replace the BCM. Hope that helps. Bill