Somthing in My 1993 chrysler Imperial keeps killing the battery. Could it be the middle overhead council that keeps doing a systems check while the car is off that could be doing it. If so how do I disable it.
You should get rid of that car right now! Oh, and by the way, I'll take it off your hands real cheap. : ) I have the twin, a '93 Dynasty with 4,100 miles. Wanted that overhead computer but it wasn't available on the Dynasty. Darn the bad luck.
I'm not sure why it won't turn off but yes, that will run the battery down. I would pull it down and check for voltage on the wires when they're unplugged from the computer. One should have 12 volts all the time for the memory circuit and a different one should only have 12 volts when the ignition switch is on. If that's what you find, check them again with the connector plugged in. With the ignition switch off, if you find voltage on two wires, something in the computer is feeding between the two circuits. A likely suspect in that case would be the diodes, (one-way valves for electricity), that protect the computer in case the battery is connected backwards. Under normal conditions those diodes don't do anything but if one shorts, I can see where it might cause the computer to remain on.
A more common problem for the battery being run down is the glove box light staying on. The tab of metal that the light switch is on gets bent from stuffing too many maps in there. All you have to do for that is to pull the tab down so the door pushes the switch button to turn the light off.