DTC P0154 - Left Front Oxygen Sensor Activity Not Detected: Condition

DTC is set when left front oxygen sensor signal voltage does not exceed .6 volt after engine is started, or stays below .6 volt for 98 seconds after engine has reached normal operating temperature. Engine speed at 1150 RPM or greater and voltage supplied to sensor heater. Possible causes are:

• Left front oxygen sensor.
• Open or short circuit between terminal No.3M on Powertrain Control Module (PCM) and terminal "A" (Green wire) on left front oxygen sensor.
• Intake air system, fuel system and/or ignition system malfunction.