Displaying Diagnostic Trouble Codes

"CHECK ENGINE" Light:

The vehicle condition monitor (VCM) message screen displays faults related to a number of vehicle systems, including brake system, cooling system, engine management and light bulbs. The same screen also displays trip computer information.

In case of 2 or more simultaneous failures, warning display and message for each fault will flash alternately every 2 seconds. An asterisk (*) will appear indicating more than one fault exists. Single faults will not flash.

If one fault of 2 or more is a brake failure (except anti-lock), a red border will surround all warning symbols. In case of anti-lock failure, border will be amber.

When a fault message occupies the screen, pressing trip computer "CLEAR" button will override fault message and display trip computer information. If "CLEAR" is pressed while COOLANT LEVEL LOW, BULB FAILURE, CIRCUIT FAILURE or WASHER FLUID LOW warnings are displayed, both warning symbol and message will be removed. An asterisk (*) will appear indicating a fault exists.

Pressing "VCM" button when fault(s) exist overrides trip computer information and displays fault warning symbol and message. If a fault occurs while trip computer information is being displayed, fault warning will override trip computer message. Pressing "CLEAR" button recalls trip computer information.

When the ECU detects certain engine management faults, the "CHECK ENGINE" lamp on the VCM is illuminated, accompanied by the "!" symbol surrounded by an amber border (except as noted above). Fault(s) are recorded in ECU memory and displayed as numerals (1 through 8) each time ignition is switched "ON" (position "II"). Fault code numbers correspond to these problems:

1. Oxygen sensor open circuit.
2. Airflow meter failure. Either open or short circuit.
3. Coolant temperature sensor failure.
4. Feedback fueling full rich.
5. Airflow meter failure. Low throttle potentiometer voltage with high airflow meter voltage.
6. Airflow meter failure. High throttle potentiometer voltage with low airflow meter voltage.
7. Feedback fueling full lean.
8. Air temperature sensor failure. Either open or short circuit.

For more information regarding the VCM and possible fault displays, refer to Instrument Panel, Gauges and Warning Indicators Testing and Inspection
and Driver/Vehicle Information Display. Testing and Inspection