Diagnostic trouble code (DTC) information

Condition 

Fig 1: Identifying Front Heated Oxygen Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

The engine control module (ECM) continuously checks the probe as it switches between rich / lean and lean / rich. The switching time is measured by checking how high or low the power consumption is. This check is carried out at fuel shut-off and at re-engagement after fuel shut-off. Diagnostic trouble code (DTC) ECM-210A is stored if the engine control module (ECM) registers a fault.

• the engine coolant temperature (ECT) is above 70°C (engine at operating temperature)
• fuel trim active
• speed above 30 km/h
• engine speed (RPM) higher than 1000 RPM.

Substitute Value 

The fuel trim is shut off.

Possible Source 

Defective front heated oxygen sensor (HO2S).

Fault symptom[s] 

Non E.