Accessing and Reading Diagnostic Trouble Codes

Diagnostics Flow Diagram.:

To enter diagnostic mode, turn ignition On, then depress Off and Warmer buttons on the Climate Control Panel (CCP). Hold buttons until all display panel segments illuminate (segment check), indicating beginning of diagnostic readout. The two display panels must be illuminated to ensure all segments are operating. Do not attempt diagnosis unless all segments appear, since an improper diagnosis could result. If any segments are inoperative, the display panel must be replaced.

When segment check is completed, any codes stored in computer
memory will be displayed on the data display as follows:



1. All ECM codes will be displayed first. Codes will be displayed with the lowest code first, followed by progressively higher codes present. All ECM codes will be prefixed with an ``E'' (EO14, EO15 etc.) before the code. If no ECM codes are stored, a ``No ECM Codes'' message will be displayed.
2. When all Electronic Control Module (ECM) codes or a ``No ECM Codes'' message has been displayed, all Body Control Module (BCM) codes will be displayed. BCM codes are prefixed with a ``B'' (BI15, BI19 etc.). If no BCM codes are stored, a ``No BCM Codes'' message will be displayed.
3. Any ECM or BCM codes displayed will also be accompanied by ``Current'' or ``History.'' ``History'' indicates the failure was not present the last time the system was monitored, while ``Current'' indicates the fault still exists.
4. At any time during the display of the ECM or BCM codes, if the Lo button on the Climate Control Panel (CCP) is depressed, the display of codes will be bypassed. If the ``Reset/Recall'' button on the Driver Information Center (DIC) is depressed, the system will exit the diagnostic mode and go back to normal vehicle operation.
5. After all ECM and BCM codes have been displayed, or if no codes are present, a decision point is reached. ``ECM'' is displayed, and the technician may select from ECM, BCM or IPC data.