- Description of On-Board Diagnostics

Data Display:

Information Center Buttons:

DESCRIPTION
The Central Control Module (CCM) uses the speedometer, odometer, and the trip monitor located on the instrument cluster to display information while in the diagnostic mode.

OPERATION
The speedometer is used to display Diagnostic Trouble Codes (DTCs) (CCM, ABS/TCS, SIR and PCM), the odometer displays data, and the trip monitor indicates the system being tested and the test which is being performed. The buttons on the Driver Information Center (DIC) are used to send instructions to the CCM when in the diagnostic mode.

Unlike other vehicle electronic systems, such as PCM, SIR, etc., there is no specific "CCM" lamp to indicate a malfunction. A DTC-setting malfunction in any of the CCM.monitored systems is indicated by "SYS" (SYSTEM ERROR) flashing in the instrument cluster trip monitor. If a malfunction does not recur within 100 ignition cycles the CCM will automatically clear the DTC.
The "SYS" indicator will flash 3 times every 15 seconds while a current-DTC malfunction is present. An exception to the "SYS" malfunction indicator is that PASS-Key� malfunctions (DTCs 51-53) will be indicated by the "SECURITY" lamp being illuminated without the "SYS" indicator flashing. If there is a Fuel Enable Data Stream (FEDS) malfunction (DTC 54), the "SECURITY" indicator and "SYS" indicator will flash together, to illustrate that the problem condition affects vehicle security.