Checking the components and wiring

Check the heated oxygen sensor (HO2S) connector. Check for contact resistance. Check for an open-circuit. Check for oxidation.

Check that the heated oxygen sensor (HO2S) is correctly installed in the exhaust system.

Try a new heated oxygen sensor (HO2S) if the above fault-tracing does not remedy the fault.

Remedy as necessary.

Other information 

• For information about signals on 5 cylinder engines, see Signal specification
• For information about signals for 6 cylinder engines:
  • For 6 cylinder engines -2001, see Signal specification
  • For 6 cylinder engines 2002-, see Signal specification
  • For 6 cylinder engines -2004, see Signal specification
  • For 6 cylinder engines 2005-, see Signal specification .
• See Heated oxygen sensor (HO2S), replacing
• See Contents

Fig 1: Identifying Front Heated Oxygen Sensor Connector Terminals

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Identifying VCT2000 Diagnostic Tool Symbol In VIDA

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 3: Identifying Front Heated Oxygen Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

• Continue 

  Refer to Verification