Rear Blower Motor Delay Turn On for 3 Minutes DTCs B0145 B0428 B3531 - keywords AC actuator auxiliary code delay HVAC module terminal

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

During the rear actuator recalibration process, auxiliary HVAC blower operation is disabled. After approximately 3 minutes, if the auxiliary HVAC control module is unable to complete the recalibration process because of an auxiliary actuator and/or circuit malfunction, auxiliary HVAC blower operation will be enabled. In this case DTCs should set in the auxiliary HVAC control module, and the rear HVAC system will run in a default mode. If the auxiliary HVAC control module is unable to complete the recalibration process, it will attempt to recalibrate the rear actuators after every ignition key cycle until the process is complete. This would result in an auxiliary blower delay of approximately 3 minutes after each key cycle.

1. If there are any DTCs, please follow the appropriate diagnostic chart.
2. Inspect pin terminal tension at the Auxiliary HVAC control and at each Actuator.
3. Repair any terminals as necessary.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.