Checking the connector

Fig 1: Engine Start Verification

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Identifying Connector(s) Reinstallation

Courtesy of VOLVO CARS OF NORTH AMERICA.

• 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 signal for the rear heated oxygen sensor (HO2S).

  NOTE:

  It may take up to approximately 3 minutes before fuel trim has begun and the signal can be read off.

  Check that the signal is within its permitted range. The signal must be free of interference and between 0.6 - 0.3 V.

  If the signal is now OK this indicates that the fault was caused by a poor connection in the connector.

  Other information: 

  • To connect the breakout box / access the control module, see Connecting the breakout box
  • To access or replace the heated oxygen sensor (HO2S), see Heated oxygen sensor (HO2S), replacing
  • For information about signals on 5 cylinder engines, see Signal description or Signal specification
  • See Contents .
  Fig 3: Identifying Heated Oxygen Sensor

  Courtesy of VOLVO CARS OF NORTH AMERICA.
  Fig 4: Identifying VCT2000 Diagnostic Tool

  Courtesy of VOLVO CARS OF NORTH AMERICA.
  Fig 5: Identifying Rear Heated Oxygen Sensor

  Courtesy of VOLVO CARS OF NORTH AMERICA.

Is the signal OK? 

• YES 

  OKAY:  Troubleshooting has been completed.

• NO 

  Refer to Checking components and wiring