Diagnostic Trouble Code (DTC) Information ECM-246B

Condition 

Fig 1: Front Heated Oxygen Sensor

Courtesy of VOLVO CARS CORPORATION

The diagnostic trouble code (DTC) is stored if the engine control module (ECM) registers that the calibration current has ceased and the front heated oxygen sensor (HO2S) signal (bank 1) is implausibly high at fuel shut-off.

Substitute Value 

• None.

Possible Source 

• Contact resistance and oxidation in the terminals
• Open-circuit in the cable for calibration current
• Damaged front heated oxygen sensor (HO2S).

Fault symptom[s] 

• Malfunction indicator lamp (MIL) lit.