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Checking the wiring and component

CAUTION:

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

Fig 1: Identifying Ignition Switch OFF Position

GLL101045

Courtesy of VOLVO CARS OF NORTH AMERICA.

Ignition off.
Check the signal cable (+) between heated oxygen sensor (HO2S) terminal #4 and control module terminal #A61 (#B1). Check the signal cable (-) between heated oxygen sensor (HO2S) terminal #3 and control module terminal #A62 (#B2). Check for a short-circuit to ground.

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
- To access or replace the heated oxygen sensor (HO2S), see Heated oxygen sensor (HO2S), replacing
- For information about signals, see ELECTRICAL SYSTEM
- See Contents .
Fig 2: Identifying Heated Oxygen Sensor
Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 3: Identifying Ohmmeter
Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 4: Identifying Rear Heated Oxygen Sensor
Courtesy of VOLVO CARS OF NORTH AMERICA.

Continue
Refer to Verification