FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Signal Missing. Permanent Fault






Signal missing. 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 on a disconnected, non-deployed airbag module. This could deploy the airbag!

- Install special tool 861 8437 SRS adapter C70 ,S70,V70 861 8437 SRS Adapter on the passenger airbag 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, see Passenger airbag module Passenger Airbag Module.

Does the diagnostic trouble code (DTC) status change?

Yes - Verification

No - Checking components and wiring

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Checking components and wiring








- Ignition off.
- Remove special tool 861 8437 SRS adapter C70 ,S70,V70 861 8437 SRS Adapter.
- Disconnect the battery negative lead.
- Disconnect the control module.

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

Check the control module connector for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check for damage carefully.
Connect an ohmmeter between passenger airbag #1 and #2. Check for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Remedy as necessary.

Other information:
- To access the control module connector, see SRS control module Service and Repair.
- A short-circuit element in the control module connector ensures that there is contact between the positive and negative leads when the control module is disconnected. Otherwise the airbag module may deploy unintentionally.









Select Continue when the fault has been remedied.

Continue - Verification

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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 FAILED

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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 - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking component

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