Procedure For Running On-Board Diagnostics

The on-board diagnostics feature was built into all Allante's. Virtually every switch and sensor on the car are connected to the on-board computer system, and can be checked through the message window in the Driver Information Combo Panel.

To enter diagnostics, key must be on, car running or not. It does not matter. Press and hold the OFF and WARMER (red) buttons on the DIC until the display changes. This is the beginning of the diagnostics mode. Any stored trouble codes will be listed, and can be copied for future analysis.
Several buttons on the AC control head are used when operating the diagnostics feature:
LO fan speed: to skip, no, or increment downward
HI fan speed: to select, yes, or increment upward
OFF: advance to next segment and enter diagnostics
WARMER (red): to increase stored parameter value and enter diagnostics
BLUE: to decrease stored parameter value
A factory service manual is required to take full advantage of the on-board diagnostics system built into your Allante'.
Pressing RESET or turning off the ignition will exit diagnostics.

HOW TO CLEAR STORED TROUBLE CODES

Enter Diagnostics by simultaneously pressing and holding the OFF and RED (warmer) buttons on your Driver Information Center air conditioning control panel for about 5 seconds, until the display changes. Diagnostics will scroll through all trouble codes that are in memory.
At ECM? Prompt, press HI (fan speed) to select if there are any ECM trouble codes stored, or LO (fan speed) to skip to next segment.
If you pressed HI, next press LO at each successive ECM prompt until ECM CODES CLEAR? message is received. Then press and hold HI until message ECM CODES CLEAR is received.
Press OFF on AC control to move to the BCM? Prompt. Press HI to select if there are BCM codes to clear, or LO to skip.
If you pressed HI, next press LO at each successive BCM prompt until BCM CODES CLEAR? message is received. Then press and hold HI until message BCM CODES CLEAR is received.
Press OFF on AC control to move to the LIGHTING? Prompt. Press HI to select if there are LIGHTING codes to clear, or LO to skip.
At LIGHTING CLEAR CODES? Prompt, press and hold HI (fan speed) to clear any stored Lighting trouble codes stored.
At SIR? Prompt (1990-1993), press HI to select.
At SIR CLEAR CODES?, press and hold HI fan speed to clear codes.
Press RESET to escape or turn off key.