SFI SYSTEM, Diagnostic DTC:P0135

DTC Code DTC Name
P0135 O2 Sensor Heater Circuit Bank 1 Sensor 1

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0135 O2 Sensor Heater Circuit Bank 1 Sensor 1

DTC Detection Condition


    Enable Criteria

  • Engine run time 60 seconds or more


    Malfunction Criteria

  • Set when the heater output is greater than 1.9 A or less than 0.25 A for 7.5 seconds


    Diagnostic Mask

  • The MIL will be illuminated if these faults are present for 2 consecutive trips


    Monitor

  • Continuous


    Potential failure modes

  • Sensor connector and wiring should be checked for corrosion and loose connections

  • Open or short in heated oxygen sensor (sensor 1) heater circuit

  • Heated oxygen sensor (sensor 1)

  • Driver side junction block assembly

  • ECM

 Comes on DTC stored

MONITOR DESCRIPTION

The oxygen sensor is electrically heated to improve response after start.

The sensor consists of a zirconia electrode between two platinum plates. When zirconia comes into contact with oxygen, it becomes an electrical conductor. The exhaust gases pass through louvers in the sensor. One plate is in contact with the outside air and the other plate is in contact with the exhaust gases. The platinum plate in contact with the air is electrically negative due to the oxygen in the atmosphere and the plate in contact with the exhaust gases is electrically positive. This will cause a difference in electrical potential to develop between the two plates. Thus the voltage across the platinum plates ranges approximately from 100 millivolts to 900 millivolts, depending on the oxygen content of the exhaust gases. Thus when the air/fuel mixture is rich, the oxygen sensor output will be high. If the air/fuel mixture is lean, the oxygen sensor output will be low.

WIRING DIAGRAM

Refer to DTC P0131.

Click here

CAUTION / NOTICE / HINT

Tech Tips


  • Sensor 1 refers to the sensor closest to the engine assembly.

  • Sensor 2 refers to the sensor farthest away from the engine assembly.

  • Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. INSPECT HEATED OXYGEN SENSOR (SENSOR 1) (HEATER RESISTANCE)


    1. Inspect the heated oxygen sensor (sensor 1).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HEATED OXYGEN SENSOR (SENSOR 1)

    OK

  2. CHECK TERMINAL VOLTAGE (HEATED OXYGEN SENSOR (SENSOR 1))


    1. B0045MNC06
      *a

      Front view of wire harness connector

      (to Heated Oxygen Sensor (Sensor 1))

      Disconnect the heated oxygen sensor (sensor 1) connector.

    2. Turn the engine switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      B37-2 (+B) - Body ground Engine switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT EFI MAIN RELAY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR (SENSOR 1) - ECM)


    1. Disconnect the B37 heated oxygen sensor (sensor 1) connector.

    2. Disconnect the B142 ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B37-1 (HT1A) - B142-20 (HT1A) Always Below 1 Ω
      B37-1 (HT1A) or B142-20 (HT1A) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  4. CHECK WHETHER DTC OUTPUT RECURS


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Clear DTCs.

    5. Turn the engine switch off and wait for at least 30 seconds.

    6. Turn the engine switch on (IG).

    7. Turn the GTS on.

    8. Start the engine.

    9. Allow the engine to idle for 20 minutes or more.

    10. Enter the following menus: Powertrain / Engine / Trouble Codes.

    11. Read the DTCs.

      Result
      Result Proceed to
      DTC is not output A
      DTC P0135 is output B

    A

    CHECK FOR INTERMITTENT PROBLEMS

    B

    REPLACE ECM Click here

  5. INSPECT EFI MAIN RELAY


    1. Inspect the EFI MAIN relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE EFI MAIN RELAY

    OK

  6. CHECK HARNESS AND CONNECTOR (EFI MAIN RELAY - HEATED OXYGEN SENSOR (SENSOR 1))


    1. Remove the EFI MAIN relay from the No. 2 engine room relay block assembly.

    2. Disconnect the B37 heated oxygen sensor (sensor 1) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B37-2 (+B) - 3 (EFI MAIN relay holder) Always Below 1 Ω
      B37-2 (+B) or 3 (EFI MAIN relay holder) - Body ground and other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    CHECK ECM POWER SOURCE CIRCUIT Click here

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR