Digital Climate Control partially dead on 85 fleetwood

[BrentNewland]

The digital climate control and fuel data center on my 85 fleetwood FWD HT4100 is mostly dead. I can see the info on the displays when I first turn the key to the on position (and it seems to be correct - tells me miles left until empty, but that's the only one I've looked at). But a fraction of a second later, it turns off, and I have to turn the key to off and wait a few seconds for it to do that again. It happened after trying to install an aftermarket HU (stock was stolen before car was purchased). The controls for the climate control have no effect.

Has anyone had a similar problem or have a solution? The panels themselves shouldn't be bad if I can see info on them at some point, and if I can see correct data then the BCM shouldn't be bad. I've checked the fuses (but that shouldn't be the problem either, or it should never turn on).

[carnut]

Had this happen on my 88 coupe after an aftermarket radio install. The radio display was wired incorrectly and it shorted out the BCM illumination circuitry. The stock radio display is lower than 12 volts. 12 volts applied to the car harness shorts out the BCM, which controls the display illumination.