Diagnosis

The airbag system is constantly monitored by a diagnosis unit in the control unit. If a fault occurs this is indicated by a monitor lamp in the instrument cluster.

The airbag monitor lamp comes on for approx. 5 seconds when the ignition is switched on, then goes out again. During starting, the monitor lamp lights up once more for approx. 5 seconds.

Should the monitor lamp not come or should it remain lit, there is a fault in the airbag system. The fault can be read with system tester 9288.

Note

The control unit requires approx. 70 seconds to identify all the faults in the system, so the ignition must be switched on for at least this amount of time.

The diagnosis unit of the control unit differentiates between faults which are constantly present and faults which have occurred but are now no longer present.

Porsche System Tester 9288

The Porsche system tester 9288 can be used to read the fault memory of the airbag control unit and the time out of operation since the first fault was recorded.

Diagnosis Procedure

Switch off ignition.

Connect Porsche system tester 9288 to diagnosis socket in the car. Press button to switch on Porsche system tester. Input vehicle model. Switch on ignition.

Follow further tester instructions up to display "Installed systems".

Input AIRBAG.

Input FAULT MEMORY.

Once the number of faults has been displayed, reading-out of the first stored fault is carried out. A maximum of 11 faults can be stored and read out.

Airbag - Special Tools 9516 and 9516/1

If a fault is indicated in ignition pill circuit 1, 2 or 3 during diagnosis, the respective fault can be identified using Special Tools 9516 and 9516/1.

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9516 9516/1

If a fault is indicated as being present in an ignition pill circuit, erase the fault memory and connect Special Tool 9516 to the plug-in contact on the airbag unit. After switching on the ignition the monitor lamp will show whether the fault is still present or not.

If the fault is:

- no longer present - replace the airbag unit.

- still present - a) in ignition pill circuit 2 or 3 (passenger's side) the cable harness complete with control unit must be replaced.

- b) in ignition pill circuit 1 (driver's side) there could be a further fault in the contact unit (steering column switch).

To test the contact unit connect Special Tool 9516/1 to the plug-in connection of the contact unit and repeat the process.

If the fault is:

- no longer present - replace the contact unit.

- still present - replace the cable harness with control unit. Caution:

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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