How do you reset a 1990 Cadillac DeVille computer system after self-servicing?

Answer 1

I had my 1991 sedan deville towed the other night, and the tow truck driver told me that the cars climate control is the cars computer also, said you need to push those buttons in a certain sequence, or a couple at the same time, he just didnt know what to push. i checked that with Cadillac and they agreed, they just didnt know how to do it either, go figure. ive also heard disconecting the negative terminal of your battery then reconecting a few seconds after will do the trick. I also read in a manual (i havnt been able to find since) that reseting the computer is done by idleing the car for a certain period of time in park and then in drive while the climate control is set to "off". when/if i find that again i will put it in. a little.

ok found it. If you lose battery power or the battery is disconecte, your cars computer must be programmed. it takes just over 20 minutes to do it.

If you want to do it your self, here's how:

1. Apply the parking brake
2. Make sure the front wheels are straight.
3. Turn off the electronic climate control.
4. Start the engine in park and let it idle for 15 minutes.
5. Put your foot on the brake pedal, shift the transaxle to Drive and let it idle for 3 minutes or more. do not accelerate the engine.
6. With the vehicle in drive, turn the electronic climate control to "auto" and let engine idle for 3 minutes or more.
7. Turn the engine off.
8. Now your computer is programmed.

That is from the manual to my 1991 caddy deville. I guess disconnect your battery then follow those steps. Good luck

Actually most Cadillacs use the same method to reset the ECM and the BCM. Assuming that the the problem that caused the check engine light to come on is not a hard fault. With the engine off and the ignition switch (the key) turned to run go to the climate control buttons and press the 'OFF' and 'Warmer' button and the same time until you see the fuel control panel change to all 8s then let go of the climate control buttons. The fuel panel will give a readout of all the failure codes recorded up to the last 50 times. If the cause of a failure code has been resolved turn the ignition switch off then turn it back on to 'run' then while holding the 'Off' button on the control panel press on the 'HI FAN' button on the climate control panel at the same time. Hold the two buttons for about 5 seconds. Turn the ignition switch off for a few seconds and then start the engine again. Allow the enging to reach normal operating temperature or drive it about 4 or 5 miles which will cause the engine to reach normal operating temperature quicker. Observe the check engine light to see if it illumintes again. There are many operational checks that can be made through these control panels both with the engine off and while running. It is best to have the manufacturers shop service manual to do many of these tests properly. Cadillac shop service manuals from the dealer will cost around $100.00. You can often get the manual used through eBay or some other source for half price or less.