Entering Diagnostics
WARNING: This page is about a different car, the 1990 Cadillac Allante. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Operating the vehicle in diagnostics for extended time periods without the engine running or without a battery charger will cause the battery to run down and possibly relate false diagnostic information, or cause a no start condition. To ensure proper operation, attach a battery charger if vehicle is to be operated in diagnostics without engine running for periods longer than 1/2 hour.
To enter diagnostic mode, turn ignition to ON position. Press "OFF" and "WARMER" buttons on the Climate control panel simultaneously, and hold until a segment check is displayed on IPC and COMBO panel. See Fig 1 - Fig 5 .
NOTE:
If vehicle will not go into diagnostic mode, or one or more of the LED segments do not illuminate, go to SELF DIAGNOSTIC SYSTEM CHECK
.