How do you check the error codes on a 1988 Cadillac?

Answer 1

on most 1988 Cadillacs, turn the key ON and on the climate control panel, hold both OFF and WARMER for a few seconds. The screen will flash up the codes as a series of letter + 3 number codes, indicating each as either CURRENT or HISTORY, ending with a menu entry (usually "ECM?"). To reset the codes, press the FAN-LO button to change the display until it reads "ECM?," then press FAN-HI; cycle with FAN-LO until you see ECM CLEAR CODES? and press FAN-HI again. Then tap the OFF button twice and cycle through the first menu with FAN-LO until it reads BCM? and hit FAN-HI; again, cycle with FAN-LO to BCM CLEAR CODES? and press FAN-HI. To exit the menus and restore normal displays, tap OFF until you reach the main menu, then tap OFF button 3-4 times rapidly. (Or, just turn off the key or start the motor, either will restore the display.)

on the diagnostic plug under the center of the dash, use a jumper wire to short the lower two right hand connectors together after the check engine light has come on and the car is running. the check engine light will then flash the codes as: flash flash flash pause flash flash flash flash long pause - would be a code 34, each code will flash 3 times before moving on to the next code and after the last code, will start over with first code. you will then have to look up the code to find the problem behind it