Diagnosis/Troubleshooting With the System Tester

Important information on diagnosis/troubleshooting with the system tester 9288

A precondition for troubleshooting is that the test person

- knows the positions of the components as well as the functions and technical relationships of the systems to be tested (model information)

- can read and evaluate Porsche circuit diagrams

- knows the functions of circuits and relays

- knows how to operate and evaluate test devices such as oscilloscopes, voltmeters, ohmmeters and ammeters.

Important:

If the control unit connector or battery is disconnected, the fault memory will be cleared.

If the battery is disconnected, system adaption of the DME is also cleared.

The fault text in the display does not necessarily point to a fault in this component, but may also indicate a fault in the corresponding control unit and the connecting leads (paths) between the components and control unit.

No troubleshooting in the form of connector disconnection etc. must be performed before reading out the fault memory, because this may be stored as a fault in the fault memory.

Information on fault display

If fault not present appears on the tester display, this may mean:
- Fault not present at the time of testing (loose contact)
Remedy: Check the fault path. In other words, perform a visual inspection of the wiring harness and plug-in connection.
- Test conditions under which the faults occurred are not satisfied (e.g., test speed is not reached)
Remedy: Satisfy the conditions

Signal not plausible:
The signal of the monitored component does not fit in the tolerance band of the calculated value in the control unit