Fault Code 0166

Fault code 0166

Electronic ignition starter switch

Diagnostic conditions
- Internal function test on KESSY control unit

Possible fault causes
- No signal/communication (no communication between control unit and ignition starter switch)
- Electrical fault in circuit (connector contact problem)
- Short circuit to ground or open circuit in lines
- Short circuit to B+ or open circuit in lines
- Short circuit to ground
- Short circuit to B+
- Open circuit in lines
- Electronic ignition starter switch faulty
- Control unit faulty

Affected pins
- Ignition starter switch connector: Pin 1, Pin 2, Pin 3, Pin 4, Pin 5, Pin 6, Pin 7, Pin 8, Pin 9, Pin 10, Pin 11, Pin 12
- Control unit connector A: Pin 19, Pin 33, Pin 35, Pin 37, Pin 40, Pin 41, Pin 52, Pin 53, Pin 55, Pin 57
- Control unit connector B: Pin 4, Pin 5

Diagnosis/troubleshooting

NOTE:
Visual inspection: In the next troubleshooting section, please check first that the affected pins on the KESSY control unit plug connection are neither damaged nor corroded. The wiring and connectors of the affected components must also be checked for external damage and correct contacts. Repair damaged or corroded pins if possible, otherwise replace affected pins. Repair or replace damaged wires.

NOTE: Conventional diagnosis/troubleshooting cannot be performed for the fault type 'short circuit to B+', which is displayed using the 'F8' key in the 9588 Porsche System Tester II. The reason for this is that the ignition cannot be switched on when there is no control unit connected. As a result, it is not possible to differentiate uniquely between a short circuit to terminal 30 and a short circuit to terminal 15. A thorough visual inspection of components and wiring must therefore be carried out before replacing a control unit.

NOTE: The resistance values specified below are based on an ambient temperature of 20 °C.

Connector for ignition starter switch






Ignition starter switch