DTC P0135: O2 Sensor 1/1 Heater Failure: Description

Circuit is monitored with engine idling immediately after a cold start (engine temperature less than 147°F and battery temperature plus or minus 27°F (3°C) of engine temperature. DTC is set when O2 sensor 1/1 voltage is more than 3 volts for 30-90 seconds. Possible causes for DTC to set are: O2 sensor 1/1 connector damaged, O2 sensor 1/1 ground circuit open, ASD relay output circuit open, O2 sensor 1/1 failure or O2 sensor 1/1 heater failure.