Clearing Diagnostic Trouble Codes

On Board Diagnostic Flow Diagram:

Climate Control Driver Information Center:

DIAGNOSTIC CODE DISPLAY

To enter diagnostic mode, proceed as follows:

1. Turn ignition "ON".

2. Depress the "OFF" and "WARMER" buttons on the Climate Control Panel simultaneously and hold until the segment check appears on the Instrument Panel Control (IPC) and the CCDIC.

SEGMENT CHECK

The purpose of illuminating the IPC and the CCDIC 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.

TROUBLE CODE DISPLAY

After the segment check, any trouble code stored in computer memory will be displayed. Codes may be stored for the PCM, BCM, Lighting, SIR ABS/TCS, or RTD systems.

SELECTING THE SYSTEM

After trouble codes have been displayed, a specific vehicle system (PCM, BCM, Lighting, SIR, ABS/TCS, or RTD) may be selected for testing.

The first available system will be automatically displayed (i.e. PCM?). While selecting the system to test, any of the following actions may be taken:
1. Depressing the "HI" button on the CCDIC will select the displayed system for testing.
2. Depressing the "LO" button on the CCDIC will display the next available system selection. This allows the display to be stepped through all system choices. This list of systems can be repeated following the end of the system list.
3. Depressing the "OFF" button the CCDIC will stop the system selection process and return the display to the beginning of the trouble code sequence.

SELECTING THE TEST TYPE

Having selected a system, the first available test type will be displayed (i.e. PCM DATA?). While selecting a specific test type, any of the following actions may be taken:
1. Depressing the "HI" button on the CCDIC will select the displayed test type. At this point the first of several specific tests will appear.
2. Depressing the "LO" button on the CCDIC will display the next available test type for the selected system. Step through this display until "CLEAR CODES?" is displayed.
3. Depressing the "OFF" button on the CCDIC will stop the test type selection process and return the display to the next available system selection.

DATA, INPUTS, OUTPUTS, OVERRIDES, CLEAR CODES or SNAPSHOT

^ Selection of the "DATA?", "INPUTS?", "OUTPUTS?", or "OVERRIDE?" test types will result in the first available test being displayed. Four characters of the display will contain a test code to identify the selection. The first two characters are letters which identify the system and test type (i.e. PD for PCM DATA) and the last two characters numerically identify the test (i.e. PD01 for Throttle Position).

While selecting a specific test, any of the following actions may be taken:
1. Depressing the "HI" button on the CCDIC will display the next larger test number for the selected test type. If this button is pressed with the highest test number displayed, the lowest test number will then appear.
2. Depressing the "LO" button on the CCDIC will display the next smaller test number for the selected test type. If this button is pressed with the lowest test number displayed, the highest test number will then appear.
3. Depressing the "OFF" button on the CCDIC will stop the test selection process and return the display to the next available test type for the selected system.
4. Depressing the "LO" button after override is displayed will put the system into "ECM CLEAR CODES?" display. Depressing "HI" or "LO" at this point will either clear codes or bypass code clearing.

^ Selection of "CLEAR CODES?" test will result in the message "CODES CLEARED" being displayed along with the selected systems name. This message will appear for 3 seconds and then return to the next available test type.

EXITING DIAGNOSTIC MODE

To get out of the diagnostic mode, depress the "AUTO" or "DEFOG" button, or turn the ignition switch "OFF". Trouble codes are not erased when this is done.