DTC P0154: Left Front Heated Oxygen Sensor, Insufficient Activity Detected: Condition

DTC is set when left front heated oxygen sensor signal voltage does not exceed .55 volt after engine is started, or stays less than .55 volt for 99 seconds after engine has reached normal operating temperature. Engine speed at 1150 RPM or greater. Possible causes are:

• Left front heated oxygen sensor.
• Open or short of Yellow wire between terminal No. 3M on Powertrain Control Module (PCM) and terminal "A" on left front heated oxygen sensor. See Figure .