Diagnostic trouble code (DTC) information

Condition

Fig 1: Identifying Front Heated Oxygen Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

Diagnostic trouble code (DTC) ECM- 2100 is stored if the engine control module (ECM) registers that the current from the heated oxygen sensor (HO2S) deviates from 0 mA excessively (with " even driving" the current should be around 0 mA (lambdaλ =1).

Substitute Value

Fuel trim shut off.

Possible Source

Too high (positive) current:

short-circuit to ground in the signal cable
defective heated oxygen sensor (HO2S)
defective IC circuit (in engine control module (ECM)).

Too low (negative) current:

short-circuit to supply voltage in the signal cable
defective heated oxygen sensor (HO2S)
defective IC circuit (in engine control module (ECM)).

Fault symptom[s]

Non E