Transfer Box

Fault code 2057

Voltage supply to brake for servo motor (A)

Diagnostic conditions
- Ignition on
- Internal transfer box control module function test
- Engine running
- Selector lever position 'P'
- Engage longitudinal lock/gear reduction

Possible cause of fault
- 'Short circuit to B+': short circuit in wiring harness (brake for servo motor continuously activated)
- 'Short circuit to B+': control unit faulty (brake for servo motor continuously activated)
- 'Short circuit to ground': short circuit in wiring harness (brake for servo motor does not activate)
- 'Short circuit to ground': short in servo motor winding or short circuit in servo motor leads (brake for servo motor does not activate)
- 'Short circuit to ground': control unit faulty (brake for servo motor does not activate)

Affected pins
Transfer box control module plug:
- Pin 21 'supply voltage to brake for servo motor (A)', to pin A2 of 'servo motor plug A'

Diagnosis/troubleshooting

NOTE:
Visual inspection: In the next troubleshooting section, please check first that the affected 'pins' of the transfer box control unit plug connection and the 'pins' of the plug connections on the servo motor are neither damaged nor corroded. Remove any soiling or corrosion/ oxidation. Replace damaged parts/wires.

NOTE:
Control unit replacement: Before replacing the 'transfer box control unit', the ground connections, power supply and plug connections on the control unit must be checked as OK. Please observe the coding of the control module. After the test drive, read out the fault memory with the 9588 Porsche System Tester II again. Additional causes of faults that could damage the 'transfer box control unit' should be detected and remedied.

Troubleshooting fault type: 'short circuit to B+'






Troubleshooting fault type: 'short circuit to ground'