Fault Code 1596

Fault Code 1596

Servo motor for fresh-air/recirculation valve

Diagnostic conditions
- Ignition on
- Battery voltage OK (11.4 to 14.5 V)
- Internal function test completed on air-conditioning system regulator control module

Possible causes of fault
- Short circuit to B+/ground/to each other or open circuit
- Servo motor flap stiff
- Servo motor faulty
- Air-conditioning system regulator faulty

Affected pins
- 2-zone and 4-zone air conditioning systems

Air-conditioning system regulator control module, front: Plugs A and E
- Plug A: Pin 3 Fresh-air/recirculation valve (feedback signal lead, servo motor for fresh-air/recirculation valve)
- Plug A: Pin 17 Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve OPEN)
- Plug A: Pin 18 Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve CLOSED)
- Plug E: Pin 1 5 V reference voltage
- Plug E: Pin 8 Ground signal
- Manual air conditioning

Air-conditioning system regulator control module, front: Plug A
- Plug A: Pin 19 Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve OPEN)
- Plug A: Pin 20 Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve CLOSED)

Diagnosis/troubleshooting
- 2-zone and 4-zone air conditioning systems

Work Instruction 1 - 3:

Work Instruction 4 - 5:

Work Instruction 5 - 10:

Work Instruction 1 - 3:

Work Instruction 4 - 6: