1993 Cadillac deville 4.9L climate control stuck

[ljohnson]

Why is my climate display window blacked out and is stuck on 75 degrees F? also my controls are not responding.
After about 10 min the display window lights up and everything is fine until the car is turned off for more than 30 min.

[carriedi]

it sounds like you have a problem with the control panel but... you have to check all the other parts connected to the panel in the system. electronic climate control programmer, body control module, PCM...

you need to see if you have power and grounds all working normally and the communications with the other modules are working when the HVAC is not turning on. So, you may need to take this problem to a shop. You can check for codes by holding "OFF" and "WARMER" buttons down when you turn the key on until the display reads "8.8.8" (key on engine off) When the "8.8.8" comes on let the buttons go and watch for any codes that come up on the display. "E" codes are for the engine. Or "E.E" if there are no PCM codes or the PCM code list os over. "F" codes are for the BCM. and it goes just like the PCM part.