Signal Missing - Permanent Fault

Signal missing. Permanent fault

Checking the connector




- Ignition off
- Check the heated oxygen sensor (HO2S) connector. Check for contact resistance and oxidation
- Reinstall the components, reconnect the connectors etc.
- Start the engine. Allow the engine to idle.
Read off the diagnostic trouble code (DTC) status for the front heated oxygen sensor (HO2S).
The text " NOT READY" is displayed if the diagnosis is running.

Other information
- Checking wiring and terminals Checking Wiring And Terminals
- To access or replace the heated oxygen sensor (HO2S), see
- For information about signals, see Signal specification Signal Description / Specification













Is "FAULT NOT DETECTED" displayed?

Yes - Fault Found

No - Checking components and wiring

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Checking components and wiring
Check the resistance of the heated oxygen sensor (HO2S) between terminals #3 and #4.
Check the signal cable between heated oxygen sensor (HO2S) terminal #4 and control module terminal #A18 (#A18). Check the power supply between system relay terminal #3 and heated oxygen sensor (HO2S) terminal #3. Check for an open-circuit.
Remedy as necessary.

Other information
- Checking wiring and terminals Checking Wiring And Terminals
- To connect the breakout box and access the control module, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To access or replace the heated oxygen sensor (HO2S), see
- For information about the resistance values, see Component specifications Specifications
- For information about signals, see Signal specification Signal Description / Specification













Continue - Verification

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Verification




Verification

Verification

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




- Ignition off
- Reinstall the components, reconnect the connectors etc.
- Test drive the car according to the TRIP schedule, see Verifying repairs Verifying Repairs
- Do not switch off the engine after the test drive
- Connect the car to VIDA again. Read off the diagnostic trouble code (DTC) status for the front heated oxygen sensor (HO2S)
- There must not be any faults when the diagnostic is complete.









Was a fault detected?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFICATION FAILED - Fault-tracing information

VERIFIED - Fault Found

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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 the connector

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