Faulty Signal. Permanent Fault

2004 Volvo S80 L6-2.9L Turbo VIN 91 B6294TSECTION Faulty Signal. Permanent Fault





Faulty signal. Permanent fault

Replacing the component




- Ignition off.
The control module has registered a fault in the heated oxygen sensor (HO2S). Try a new heated oxygen sensor (HO2S). See Heated oxygen sensor (HO2S), replacing Heated Oxygen Sensor (HO2S), Replacing.





Continue - Verification

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Verification




Verification

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








- Ignition off
- 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 underway.









Is NOT DETECTED displayed?

Yes - Verification completed

No - 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 - Exit Fault-Tracing

No - Attempt New Test

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Attempt New Test - Replacing the component

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RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.