P0036 - P0056
Heated oxygen sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature.

Voltage is provided to the heater by the ignition 1 voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the engine control module (ECM).

The ECM commands the heater ON or OFF to maintain a specific HO2S operating temperature range. The ECM monitors the voltage on the HO2S heater low control circuit for heater fault diagnosis. If the ECM detects that the HO2S heater low control circuit voltage is not within a specified range, DTC P0036 sets for HO2S bank 1 sensor 2, or DTC P0056 sets for HO2S bank 2 sensor 2.

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  • Guest - Aurora

    MY Saturn Aura 2007 Haves a check engine since for almost a week and we have a question was does P0060 sensor mean?

  • Guest - peeler godfrey

    my toyota hummer bus is not bringing out current.please what can i do

  • Guest - Tony

    In reply to: Guest - peeler godfrey

    Not sure what that means- 'not bringing out current'

  • Guest - David

    my 2012 Chevy cruze last week was jumping in and out of gear with loss of power so i parked it went to drive it and still something off and the check engine light came on and its throwing a p0036 code could that be the cause of the jumping in and out of gear?

  • Guest - jose

    i have a code po0056 on my 05 oontiac g6

  • Guest - Stan

    In reply to: Guest - jose

    P0056 is Oxygen sensor Bank 2 sensor 2 heater circuit. Check all fuses. If good, the o2 sensor heater element is bad, so replace the oxygen sensor.

  • Guest - Guest


  • Guest - Tom

    In reply to: Guest - Guest

    <br />02 sensor located is exhaust in the. 1 before converter, or 3 and after 1 another or more. !

  • Guest - walterleaks

    What is the problem.

  • Guest - Bobby

    In reply to: Guest - walterleaks

    An oxygen sensor is not going to cause your car jerk and cut off. You might have a bad spark plug or plug wire or even a bad ignition coil or ignition module.

  • Guest - walterleaks

    Changed bank 1 and bank 2 0n my 2005 impala. Keeps jerkin and cutting off.

  • Guest - TECH

    In reply to: Guest - walterleaks

    check your canister purge valve or canister for a restrction or stuck open causing and lean or rich condition