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Signal Missing. Permanent Fault






Signal missing. Permanent fault

Checking connector








- Ignition off
- Check heated oxygen sensor (HO2S) connector for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
- Reinstall components, reconnect connectors etc.
- Start the engine and let it idle.
Read off the rear heated oxygen sensor (HO2S) signal diagnostic trouble code (DTC) status.
The text NOT READY is displayed if the diagnosis is underway.

Other information
- To access/replace the heated oxygen sensor (HO2S), see Replacing lambda probes, B5234T9, B5244T7 Replacing Lambda Probes.
- For information about signals, see Signal specification Signal Specifications.













Is FAULT NOT REGISTERED displayed?

Yes - FAULT FOUND

No - Checking wiring and components

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Checking wiring and components
Check heated oxygen sensor (HO2S) resistance between #1 and #2.
Check signal cable between heated oxygen sensor (HO2S) #2 and control module #A35 (#A35) and power supply between system relay #3 and heated oxygen sensor (HO2S) #1 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Remedy as necessary.

Other information
- Connecting the breakout box/accessing the control module, see Connecting the breakout box, B5234T9, B5244T7 Connecting The Breakout Box.
- To access/replace the heated oxygen sensor (HO2S), see Replacing lambda probes, B5234T9, B5244T7 Replacing Lambda Probes.
- For resistance values, see Component specifications [1][2]Engine Control Module.
- For information about signals, see Signal specification Signal Specifications.














Continue - Verification

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Verification




Verification

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








- Ignition off.
- Reconnect connectors, reinstall components.
- Start the engine and let it idle.
Read off the rear heated oxygen sensor (HO2S) signal diagnostic trouble code (DTC) status.
The text NOT READY is displayed if the diagnosis is underway.









Is FAULT NOT REGISTERED displayed?

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 - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking connector

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