Fault Code 2599

Fault code 2599

Servo motor for rear left temperature valve

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

Possible causes of fault
- Short circuit to B+
- Short circuit or open circuit
- Short circuit to ground
- Servo motor flap stiff
- Servo motor faulty
- Rear air-conditioning system regulator faulty

Affected pins
Air-conditioning system regulator control module, rear: Plugs B, C and D

- Plug B: Pin 14 'Left temp. valve (servo motor for rear left temperature valve OPEN)'
- Plug B: Pin 15 'Left temp. valve (servo motor for rear left temperature valve CLOSED)'
- Plug C: Pin 14 'Left temp. valve (feedback signal lead, servo motor for rear left temperature valve)'
- Plug D: Pin 3 '5 V reference voltage'
- Plug D: Pin 7 'Ground signal'

Diagnosis/troubleshooting