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Faulty Signal. Permanent Fault






Faulty signal. Permanent fault

Checking component








- Make a note of the anti-theft radio code.
- Ignition off.
- Disconnect the battery negative lead.
- Disconnect the connector from the passenger airbag.

Warning! Under no circumstances use an ohmmeter or other live measuring instrument to take readings from a disconnected, undeployed airbag module. This could deploy the airbag!

- Install the special tool 919 4732 Test dummy 919 4732 Test Dummy on the air bag connector.

Caution! The special tool must be checked and faultless. If the tool is defective it will cause errors in the diagnosis and make fault-tracing harder.

- Ignition on.
- Connect the battery negative lead.
- Read off diagnostic trouble codes (DTCs).
If the fault is in the passenger airbag, the status of the diagnostic trouble code (DTC) will have switched to an intermittent fault. Try replacing the passenger airbag and then carrying out a new verification.

Other information:
- To access / replace the passenger airbag,





Does the diagnostic trouble code (DTC) status change?

Yes - Verification

No - Checking the cable and the control module

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Checking the cable and the control module








- Ignition off.
- Disconnect the control module connector.
- Check the control module terminal pins visually.
- Check that the plastic pins are not damaged. Their function is to separate the short-circuiting element from the terminal pins when the control module is connected.
- If the plastic pins are damaged, the control module must be replaced according to Sensor module, replacement Service and Repair.
- Remove special tool 919 4732 Test dummy 919 4732 Test Dummy.
- Connect the control module connector.
- Ignition on.
Connect an oscilloscope between passenger airbag #1 and ground.
The oscilloscope should now display a spiked pulse with an interval of approximately 500 ms.
If the value deviates there is a short-circuit in the cable. Replace the cable harness.

Note! Diagnostic trouble code (DTC) SRS-007F is stored after this reading. Ignore the diagnostic trouble code (DTC), which is stored as a result of this reading.

Other information:
- To access / replace the passenger airbag,
- To access / replace the control module, see Sensor module, replacement Service and Repair.









Is the value correct?

Yes - Verification

No - No Fault Found

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Verification




Verification

Verification

Hint: After carrying out the repair, check that the fault has been remedied.




- Ignition off
- Disconnect the battery negative lead
- Reinstall the connectors, components etc.
- Ignition on
- Connect the battery negative lead.

Warning! There must not be anyone inside the passenger compartment when the battery is connected.

- Read off diagnostic trouble codes (DTCs).
The fault is no longer present if the status of the diagnostic trouble code (DTC) has changed to intermittent.





Does the status change?

Yes - VERIFIED

No - VERIFICATION FAILEDPAPER

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VERIFIED - FAULT FOUND

VERIFICATION FAILED - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.

Do you want to exit fault-tracing?

Yes - FAULT-TRACING FAILED

No - Attempt New Test

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FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Checking component

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