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 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 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, see Passenger airbag module Passenger Airbag Module.
Does the diagnostic trouble code (DTC) status change?
Yes - Verification
No - Checking the cable and the control module
-------------------------------------------------
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 SRS control module Service and Repair.
- Remove special tool 861 8437 SRS adapter C70 ,S70,V70 861 8437 SRS Adapter.
- 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-222 is stored after this reading has been taken. Ignore the diagnostic trouble code (DTC), which is stored due to this operation.
Other information:
- To access / replace the passenger airbag, see Passenger airbag module Passenger Airbag Module.
- To access / replace the control module, see SRS control module Service and Repair.
Is the value correct?
Yes - Verification
No - Fault-tracing information
-------------------------------------------------
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
------------------------
VERIFIED - FAULT FOUND
VERIFICATION FAILED - Fault-tracing information
-------------------------------------------------
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
------------------------
Attempt New Test - Checking component
-------------------------------------------------