DTC P0137: 1/2 O2 Sensor Shorted To Ground: Description

1/2 Heated Oxygen Sensor (HO2S) voltage is monitored after ignition is turned off and 1/2 HO2S cools down, and after the next time ignition is turned on, provided engine coolant temperature is less than 98°F (37°C) and ambient/battery temperature is within plus or minus 27°F (3°C) of engine coolant temperature. DTC will set in Powertrain Control Module (PCM) memory when PCM senses 1/2 HO2S voltage is less than .156 volt for 28 seconds after engine is started. Possible causes for DTC to set are: defective 1/2 HO2S, defective PCM, defective connectors or defective wiring.