Codes 5/33623 and 5/33673

Air distribution flap motor - testing

Fault symptom

Permanent: 53623
Intermittent: 33623

Conditions
Air distribution flap motor: Short circuit +12 V, open circuit, short or internal short circuit in Automatic Climate Control (ACC) control module (diagnostic trouble code 53623 - 33623 on version 2.01 arises together with 53673-33673).

Fault symptom

Permanent: 53673
Intermittent: 33673

Conditions
Air distribution damper motor: Short circuit to ground.

Testing
ISAT scan tool command: 27B

Display shows:
Desired position of the air distribution damper motor 45° ("ventilation") - 135° ("defrost").

Important : The desired position of the air distribution flap motor does not meant that the motor moves the flap to the desired position, but only that this is requested by the ACC control module. Visually check that the desired position corresponds to the actual position.







Action
1 Visually check that the air distribution damper is moved by selecting "defrost" and "ventilation" in order to move the damper across the entire setting range.
2 If the damper is not moved, disconnect the ACC control module's 39 pin connector and check the resistance in the stepping motor winding across pins 25 and 26 and across pins 27 and 28. Resistance should be about 100 Ohm at 20° C (68° F).
3 If resistance measurement is incorrect, unplug the stepping motor's 10 pin connector 98 and measure resistance directly between the motor windings. If these are incorrect, try with a new stepping motor.
4 If resistance is correct across the stepping motor windings, check for open circuit between the ACC control module's connector and the stepping motor connector. Also check for short circuit between the wiring harness and ground.
5 If all electrical measurements indicate normal readings, reinstall the connectors. Erase all diagnostic trouble codes and restart the system. If the fault is still present, try with a new stepping motor.
6 If the fault is still present, even with a new stepping motor, reinstall the old stepping motor and try with a new ACC control module.