ECD SYSTEM(w/o DPF), Diagnostic DTC:P0134

DTC Code DTC Name
P0134 Heated Oxygen (A/F) Sensor Circuit No Activity Detected (Bank 1 Sensor 1)

DESCRIPTION

In order to obtain high purification rates for the carbon monoxide (CO) and hydrocarbon (HC) in the exhaust gas, a catalytic converter is used.

The air fuel ratio sensor provides an output voltage that is proportional to the air fuel ratio that it is measuring. The air fuel ratio sensor output voltage is used as feedback to allow the ECM to control the air fuel ratio mixture. The inner surface of the air fuel ratio sensor element is exposed to outside air. The outer surface of the sensor element is exposed to exhaust gases. The sensor element is made of platinum coated zirconia and includes an integrated heating element. The zirconia element generates a small voltage when there is a large difference in the oxygen concentrations of the exhaust and the outside air. The platinum coating amplifies the voltage generation. When heated, the sensor becomes very efficient. If the temperature of the exhaust is low, the sensor will not generate useful voltage signals without supplemental heating. The ECM regulates the supplemental heating by using a duty-cycle approach to regulate the average current in the heater element.

Tech Tips

Although the DTC titles say oxygen sensor, these DTCs relate to the air fuel ratio sensor.

P0134
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
Ignition switch ON with warm engine

Open or short in wire harness of air fuel ratio sensor circuit for 2 seconds

(2 trip detection logic)

  • Open or short in air fuel ratio sensor circuit

  • Air fuel ratio sensor

  • ECM

WIRING DIAGRAM

Refer to DTC P0031 Click here.

CAUTION / NOTICE / HINT

Note


  • When replacing the ECM and/or air fuel ratio sensor, the ECM needs Registration and Initialization Click here.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips


  • When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the intelligent tester. Then after installing the new ECM, perform all of the initialization/registrations for the "Learning Values Write" function by following the instructions shown on the tester display.

  • Read freeze frame data using the intelligent tester. 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, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)


    1. Disconnect the air fuel ratio sensor connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B38-4 (AF1+) - A59-69 (AF1+) Always Below 1 Ω
      B38-6 (TR) - A59-68 (TR) Always Below 1 Ω
      B38-1 (AF1-) - A59-70 (AF1-) Always Below 1 Ω
      B38-3 (RE) - A59-71 (RE) Always Below 1 Ω
      B38-4 (AF1+) or A59-69 (AF1+) - Body ground Always 10 kΩ or higher
      B38-6 (TR) or A59-68 (TR) - Body ground Always 10 kΩ or higher
      B38-1 (AF1-) or A59-70 (AF1-) - Body ground Always 10 kΩ or higher
      B38-3 (RE) or A59-71 (RE) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  2. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor (See page ENGINE CONTROL (1ND-TV) > AIR FUEL RATIO SENSOR > REMOVAL).

    2. Perform the A/F Sensor Compensation Reset Click here.


    NEXT

  3. CHECK WHETHER DTC OUTPUT RECURS (DTC P0134)


    1. Connect the intelligent tester to the DLC3.

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

    3. Clear the DTCs Click here.

    4. Start the engine and warm it up until the engine coolant temperature reaches at 70°C (158°F) or more.

    5. Turn the ignition switch off and wait for 30 seconds or more.

    6. Turn the ignition switch to ON and wait for 5 seconds or more.

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

    8. Read the pending DTCs.

      Result
      Result Proceed to
      DTC P0134 A
      No DTC output B

    A

    REPLACE ECM Click here

    B

    END

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  5. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

  6. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the intelligent tester to the DLC3.

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

    3. Clear the DTCs Click here.

    4. Start the engine and warm it up until the engine coolant temperature reaches at 70°C (158°F) or more.

    5. Turn the ignition switch off and wait for 30 seconds or more.

    6. Turn the ignition switch to ON and wait for 5 seconds or more.

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

    8. Confirm that the pending DTC is not output again.


    NEXT

    END