SFI SYSTEM, Diagnostic DTC:P0135/21

DTC Code DTC Name
P0135/21 Oxygen Sensor Heater Circuit (Bank 1 Sensor 1)

DESCRIPTION

Refer to DTC P0130/21 Click here.

DTC No. DTC Detection Condition Trouble Area
P0135/21 Open or short in heater circuit of oxygen sensor for 0.5 seconds or more

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

  • Heated oxygen sensor heater (sensor 1)

  • MAIN relay

  • ECM

Tech Tips

Sensor 1 refers to the sensor closer to the engine assembly.

WIRING DIAGRAM

Refer to DTC P0130/21 Click here.

INSPECTION PROCEDURE

Tech Tips

Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions 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

    A01DZX6E20

    1. Disconnect the H6 sensor connector.

    2. Measure the resistance of the sensor.

      Standard resistance
      Tester Connection Condition Specified Condition
      1 (HT1A) - 2 (+B) 20°C (68°F) 5 to 10 Ω
      1 (HT1A) - 4 (E2) - 10 kΩ or higher

    NG

    REPLACE HEATED OXYGEN SENSOR

    OK

  2. CHECK WIRE HARNESS (+B VOLTAGE)

    A01E27PE01

    1. Disconnect the H6 heated oxygen sensor connector.

    2. Turn the ignition switch ON.

    3. Measure the voltage of the wire harness side connector.

      Standard voltage
      Tester Connection Specified Condition
      H6-2 (+B) - Body ground 9 to 14 V

    OK

    CHECK WIRE HARNESS (HEATED OXYGEN SENSOR - ECM, INTEGRATION RELAY (MAIN RELAY)) Click here

    NG

  3. INSPECT INTEGRATION NO.1 RELAY (MAIN RELAY)

    A01DZ2WE02

    1. Remove the integration relay from the engine room junction block Click here.

    2. Measure the voltage of the MAIN relay.

      Standard voltage
      Tester Connection Condition Specified Condition
      1J-5 - Body ground Ignition switch ON 10 to 14 V

    NG

    REPLACE INTEGRATION NO.1 RELAY

    OK

  4. CHECK WIRE HARNESS (HEATED OXYGEN SENSOR - ECM, INTEGRATION RELAY (MAIN RELAY))

    A01E0YUE10

    1. Disconnect the H6 sensor connector.

    2. Disconnect the E12 ECM connector.

    3. Disconnect the 1J connector from the engine room junction block Click here.

    4. Measure the resistance of the wire harness side connectors.

      Standard resistance
      Tester Connection Specified Condition
      H6-1 - E12-1 (HT1A) Below 1 Ω
      H6-2 (+B) - 1J-5 Below 1 Ω
      H6-1 or E12-1 (HT1A) - Body ground 10 kΩ or higher
      H6-2 (+B) or 1J-5 - Body ground 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  5. CHECK IF DTC OUTPUT RECURS


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch ON and turn the tester ON.

    3. Enter the following menus: Powertrain / Engine and ECT / DTC.

    4. Read the DTCs.

      Result
      Display (DTC output) Proceed to
      No output A
      Heated oxygen sensor circuit DTCs B

    B

    REPLACE ECM

    A

    CHECK FOR INTERMITTENT PROBLEMS