Signal Too High. Permanent Fault
Signal too high. Permanent fault
Checking component
- Make a note of the anti-theft radio code
- Ignition off
- Disconnect the battery negative lead
- Disconnect the connector from driver's 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 998 8695 TEST DEVICE 998 8695 Test Device on the driver's 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.
- Connect the battery negative lead.
- Ignition on
- Read off the diagnostic trouble codes (DTCs).
If the fault is in the passenger airbag, the DTC status should now have switched to intermittent fault. Try replacing the driver airbag and carrying out a new verification afterwards.
Other information:
- To access and replace the driver's airbag, see Steering wheel module, steering wheel and contact reel, replacement Airbag Driver's Side (SRS), Replacing.
Does the status of the diagnostic trouble code (DTC) change?
Yes - Verification
No - Checking the component and wiring
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Checking the component and wiring
- Ignition off
- Remove special tool 998 8695 TEST DEVICE 998 8695 Test Device.
- Ignition on.
Connect an oscilloscope between driver's airbag terminals #1 and #2. The oscilloscope should now display a spiked pulse with an interval of approximately 500 ms and an offset of approximately 2 V.
If the value is not correct it indicates that there is a short-circuit to battery voltage in the cable or in the contact reel.
Also take readings between ground and airbag terminal #2. The oscilloscope should read approximately 2 V.
Note! After this reading diagnostic trouble code (DTC) SRS-0079 is stored. Ignore this DTC, this is because the driver's airbag is disconnected.
Select Continue.
Continue - Checking cables
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Checking cables
- Ignition off
- Airbag disconnected
- Disconnect the control module.
- Ignition on.
Connect a voltmeter between contact reel connector A and ground.
The voltmeter should read 0 V.
If value is not correct the contact reel must be replaced.
If the value is correct the fault is in the cable, in which case the cable harness must be replaced.
Remedy as necessary.
Other information:
- To access and replace the contact reel, see Steering wheel module, steering wheel and contact reel, replacement Airbag Driver's Side (SRS), Replacing
- To access and replace the control module, see Sensor module, replacement Service and Repair.
Select Continue when the fault has been remedied.
Continue - Verification
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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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