Volkswagen Workshop Service and Repair Manuals

The Motronic control unit (J220) for the fuel injection and ignition system is equipped with a fault memory.

If faults occur in the sensors and components being monitored, they will be stored in the fault memory together with an indication of the type of fault.

Faults which only occur sporadically will have the addition "sporadic fault" on the print out. These faults will be indicated on the display by the addition "/SP". The cause of sporadic faults can be e.g. a loose contact or a brief open circuit. If a sporadic fault does not occur again within 40 engine starts, it will be erased from the fault memory.

The stored faults are output after initiating the fault display .

The fault memory must be erased once the faults have been eliminated => Page 01-29 .

The readiness code must be generated again after each time the fault memory is erased, and when the voltage supply to Motronic control unit (J220) is interrupted => Page 01-34 .

Note:

The self-diagnosis monitors only a part of the injection and ignition system. For fault finding the binder "Fault finding engine" must also be used in every case.