HVAC Module On-Demand Self Test

The HVAC Module 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 On-Demand Self Test. Make sure to retrieve continuous DTCs by carrying out the HVAC Module - Retrieve Continuous DTCs procedure before clearing any continuous DTCs.

• The HVAC Module 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 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°C- 38°C (40°F-100°F) when carrying out 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 POWER and DEFROST buttons simultaneously and release, then press the POWER 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 will display the 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 DTC CHART  and follow the ACTION for each DTC given.
• If a condition exists, but no DTCs appear during the self-test, GO to SYMPTOM CHART - CLIMATE CONTROL SYSTEMS .
• To exit the self-test and retain all DTCs, press any button except DEFROST. The HVAC module 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 door actuators to automatically recalibrate.
• Continuous DTCs will be deleted after 80 ignition switch ON cycles after the intermittent fault occurs.
• If a condition exists, but no on-demand DTCs appear during the self-test, carry out the HVAC Module - Retrieve Continuous DTCs self test.