October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.

DTC P1135: Front O2 Sensor Heater Circuit Low: Condition

PCM supplies ground to heater to complete circuit. DTC is set if PCM detects voltage less than 5.8 volts when no ground is supplied to heater. Possible causes are:

Front O2 sensor heater malfunction.
Open or short circuit in wiring.
PCM malfunction.