Fault Code 21

Fault Code 21

Ignition circuit, driver

Diagnostic conditions
- Ignition on

Possible cause of fault
- Short circuit to B+/ground or open circuit in the wiring between the driver's airbag unit and the airbag triggering unit
- Driver's airbag unit faulty
- Triggering unit for airbag faulty

Affected pins
Pins 10 and 11

NOTE: If the fault memory is cleared, the ignition must be switched off, the ignition key removed and the ignition switched on again in order to check the fault path. Only in this way is another self-test carried out.

Diagnosis/troubleshooting

Diagnosis/troubleshooting (Part 1):

Test tool 9516 instead of the driver's airbag unit

Dianosis/troubleshooting:

Test tool 9516/1 for testing the contact unit