Diagnosis/Troubleshooting

Diagnosis/troubleshooting

NOTE: It is possible to access the 'extended fault memory' with the aid of the fault memory info key F8 on the 9588 Porsche System Tester II. In addition to the freeze frames and ambient conditions, the extended fault memory also contains information about the type of fault.

Fault type

The following fault types are possible for DME:
- Signal implausible (fault type 1, Plaus)
- No signal/communication (fault type 2, Sig)
- Below lower limit (fault type 3, Min)
- Above upper limit (fault type 4, Max)

Several faults can also be stored at the same time.

Fault status

The following status types are possible:
- Present
- Not present

This information should be saved and printed with the Save key F4.

NOTE:
- Faults not present: If faults are entered but not present at the moment, it is necessary, depending on the system, to check the parts of the wiring connected to moving parts on and in the vehicle once the diagnostic conditions have been met or set. Various switching states that can cause a fault to occur must be simulated using the circuit diagram. Bear in mind that the 9588 Porsche System Tester II can show the current fault status only to a certain extent. Here, the fault frequency counter shows the operating time and mileage for the last occurrence of the fault.
- In difficult cases involving faults that are not currently present, it is a good idea to erase the fault memory (after printing it out) and check whether the fault is recorded again when a loose contact is simulated.
- Visual inspection of plug connections: As part of troubleshooting, it is important to ensure that the pins in the affected plug connections are neither damaged nor corroded, both on the component side and on the wiring-harness side. Furthermore, the wiring and the connectors must be checked for signs of external damage (cracks, etc.) and proper contact (pins not bent, spread apart or pressed into the housing). Repair damaged or corroded pins if possible, otherwise replace them. Repair or replace damage wiring. If wiring on the oxygen sensors is damaged, always replace the entire oxygen sensor.
- Visual inspection of components: As part of troubleshooting, it is important to ensure that the affected components or wiring harnesses show no visible signs of damage (e.g. cracks, deformation or chafing marks). This is particularly important for components that cannot be tested with a multimeter, e.g. the ignition bar modules, or components that can cause sporadic faults due to penetrating moisture.
- Battery positive voltage and signals: The general precondition for diagnosis/troubleshooting is a battery positive voltage in the range from 11.4 V to 14.5 V. This must be checked and ensured if necessary using a suitable battery charging device.
- Unless stated differently, specified resistance values refer to an ambient temperature of 20 °C.

End of troubleshooting (-End)

-End identifies the end of the diagnosis/troubleshooting procedure described in the troubleshooting tables. The procedure for the repair is contained in the respective repair instructions for the corresponding repair group. Once the repair has been completed, erase the DME control module fault memory, adapt the throttle adjusting unit if necessary and subsequently perform a short test or test drive to achieve the diagnostic conditions for the relevant fault. Then read out the fault memory again. The Ready statuses must be produced, depending on the country.