Reading and Clearing Diagnostic Trouble Codes

FUNCTION
The Self-diagnosis system monitors sensors and door motors. Shifting from normal mode to Self-diagnosis mode is accomplished by starting the engine (turning the ignition switch from OFF to ON) then simultaneously pressing the OFF and FOOT mode switches. The AUTOMATIC switch must be pressed within 2 seconds of pressing OFF and FOOT mode switches simultaneously. The diagnostic trouble codes are displayed on the display screen at a rate of one code per second. The display starts 30 to 60 seconds after the sequence is initiated.

PROCEDURE
1. Turn the ignition switch ON. (Engine must be running for A/C to operate.)
2. Set the interior temperature between 18 °C (65 °F) and 29 °C (85 °F).





3. Simultaneously press OFF and FOOT switches then press AUTOMATIC switch within 2 seconds.
The display screen will have a pulse tracer going around the center of the display screen, while the EATC unit checks all sensor and mode door circuits. (The system goes to OFF mode and the mode doors are recalibrated.)
If Self-diagnosis cannot be performed, go to Trouble Diagnosis Procedure for Self-diagnosis.
4. The malfunction codes are displayed at a rate of one code per second. If no malfunction code exists, 88 and all symbols will be shown on the display screen. Press the DEFROST switch to exit Self-diagnosis.
5. Verify the location of the malfunction using the Malfunction Code/Symptom Chart.





6. Press the TEMP DOWN switch to cancel Self-diagnosis without erasing malfunction codes.





7. After the malfunctions are repaired, erase the malfunction codes by pressing the DEFROST switch.
8. Perform Self-diagnosis again to verify that no malfunction codes exist.