HVAC Module - Electronic Automatic Temperature Control (EATC) On-Demand Self-Test

HVAC MODULE - ELECTRONIC AUTOMATIC TEMPERATURE CONTROL (EATC) ON-DEMAND SELF-TEST

The HVAC Module - Electronic Automatic Temperature Control (EATC) On-Demand Self-Test will retrieve on-demand (hard fault) DTCs only, it will not retrieve continuous DTCs. Continuous DTCs can be cleared when exiting the HVAC Module - Electronic Automatic Temperature Control (EATC) On-Demand Self-Test. Make sure to retrieve continuous DTCs by carrying out the HVAC Module - Electronic Automatic Temperature Control (EATC) - Retrieve Continuous DTCs procedure before clearing any DTCs.

- The HVAC Module - Electronic Automatic Temperature Control (EATC) On-Demand Self-Test will not detect concerns associated with data link messages like engine coolant temperature or vehicle speed signals. A scan tool must be used to retrieve these concerns.
- The HVAC Module - Electronic Automatic Temperature Control (EATC) On-Demand Self-Test will detect concerns in the system control functions and will display on-demand (hard fault) DTCs for concerns that are present during the self-test. The vehicle interior temperature should be between 4°-38°C (40°-100°F) when performing the self-test. If the temperatures are not within the specified ranges, false DTCs may be displayed.
- The self-test can be initiated after cycling the ignition switch from OFF to ON. Normal operation of the climate control system stops when the self-test is activated.
- To enter the self-test, press the OFF and FLOOR buttons simultaneously and release, then press the AUTO button within 2 seconds. The display will show a flashing blower icon for 20 seconds, after which all vacuum fluorescent segments will be displayed if there are no on-demand DTCs present. If DTCs are present the HVAC module - EATC will display "00 00" and then on-demand DTCs. Record all DTCs displayed.
- If any DTCs appear during the self-test, carry out the diagnostic procedure. Refer to the HVAC Module - Electronic Automatic Temperature Control (EATC) Module DTC Chart and follow the ACTION for each DTC given. Diagnostic Trouble Code Tests and Associated Procedures
- To exit the self-test and retain all continuous DTCs, press any button except DEFROST. The HVAC module - EATC will exit the self-test and retain all DTCs.
- Always exit the self-test before powering the system down (system turned OFF). Once the self-test is exited the ignition switch must remain ON for at least 30 seconds to allow the temperature blend door actuators to automatically recalibrate.
- If a condition exists but no DTCs appear during the self-test, GO to Symptom Chart - Climate Control Systems Condition: The EATC system is inoperative, intermittent or incorrect operation. Symptom Chart - Climate Control Systems