Displaying & Reading Trouble Codes

Diagnostic Flow Diagram - Part 1 Of 3:

Diagnostic Flow Diagram - Part 2 Of 3:

Diagnostic Flow Diagram - Part 3 Of 3:

NOTE: For the purpose of the test, the diagnostic procedures may refer to the Powertrain Control Module (PCM) as the ECM or Engine Control Module.


OPERATING ON-BOARD DIAGNOSTIC SYSTEM

Electronic Climate Control (ECC) Panel:

Fuel Data Center:

To enter diagnostic mode, proceed as follows:
1. Turn ignition "ON".
2. Depress the "OFF" and "WARMER" buttons on the Electronic Climate Control (ECC) simultaneously and hold until the segment check appears on the Fuel Data Center (FDC).


SEGMENT CHECK
The purpose of illuminating the panels is to check that all segments of the LED displays are working. The turn signal indicators DO NOT light during this check. If any of the segments are inoperative, the affected display panel will need to be diagnosed.


SYSTEM READY - CODE .7.0
Code .7.0 is used as a decision point in the diagnostic sequence. When Code .7.0 is displayed on the display, the technician may select the diagnostic features that he wants to perform. This is the hub of the diagnostic routines. Follow the appropriate procedure to return to this point after an action is performed.


TROUBLE CODE DISPLAY
After the segment check, any trouble code stored in computer memory will be displayed on the "Fuel Data Center." Display of the trouble codes will begin with an "8.8.8" for one second. A "..E" will then be displayed for PCM/ECM HISTORY codes (if any exist), then a ".E.E" for PCM/ECM HARD codes. After the PCM/ECM codes display the BCM codes are displayed with the following prefix; "..F" for BCM HISTORY codes, and a ".F.F" for BCM HARD codes. After all codes have been displayed or if no trouble codes are stored, ".7.0" will appear on the "Data Center" display.




STATUS LIGHTS
While in diagnostics, the displays on the ECC may be used to indicate the status of various inputs and operating conditions. The meaning of each word or symbol on the panel will change depending on whether the BCM or PCM system level is selected.



EXITING DIAGNOSTIC MODE
To get out of the diagnostic mode, depress the "AUTO" button or turn the ignition switch "OFF" for 10 seconds. The temperature setting will reappear in the display panel. Trouble codes are not erased when this is done.