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






Signal missing. Permanent fault

Checking components and wiring

Caution! Do not apply rust solvent spray or grease to the heated oxygen sensor (HO2S) connector.

Check the signal cable (+) between heated oxygen sensor (HO2S) terminal #1 and control module terminal #A41 (#A41). Check the signal cable (-) between heated oxygen sensor (HO2S) terminal #5 and control module terminal #A42 (#A42). Check for a short-circuit to each other.
Check the power supply to heated oxygen sensor (HO2S) terminal #3 and the signal cable between heated oxygen sensor (HO2S) terminal #4 and control module terminal #A18 (#A18). Check for a short-circuit to the other cables for the heated oxygen sensor (HO2S).
Try a new heated oxygen sensor (HO2S) if the wiring is OK.
Remedy as necessary.

Other information
- To connect the breakout box / access the control module, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To access or replace the heated oxygen sensor (HO2S) for the C70, S70, V70 -2000 and V70XC, see Adapter wiring switch, replacing Adapter Wiring Switch, Replacing. For other models, see Heated oxygen sensor (HO2S), replacing Heated Oxygen Sensor (HO2S), Replacing
- For information about signals on 5 cylinder engines, see Signal specification Signal Description / Specification
- For information about signals on 6 cylinder engines, see Signal specification Signal Description / Specification
- Checking wiring and terminals Checking Wiring And Terminals.














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 for a maximum of 5 minutes.
Read off the front heated oxygen sensor (HO2S) signal diagnostic trouble code (DTC) status.
The text NOT READY is displayed if 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 - FAULT-TRACING FAILED

No - Attempt New Test

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FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Checking components and wiring

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