Replacing component

Fig 1: Identifying Ignition OFF

Courtesy of VOLVO CARS OF NORTH AMERICA.

Ignition off.
The control module has registered a fault in the heated oxygen sensor (HO2S). Try a new heated oxygen sensor (HO2S) 5 cylinder according to Replacing lambda probes or 6 cylinder engines according to Heated oxygen sensors (HO2S), replacing .

Fig 2: Identifying Rear Heated Oxygen Sensor
Courtesy of VOLVO CARS OF NORTH AMERICA.