ECD SYSTEM, Diagnostic DTC:P0030

DTC Code DTC Name
P0030 HO2S Heater Control Circuit Bank 1 Sensor 1

DESCRIPTION

The air fuel ratio sensor is a broadband air fuel ratio sensor. The broadband air fuel ratio sensor measures the remaining oxygen in the exhaust gas. Fluctuations in the value of the remaining oxygen are sent to the ECM as a voltage signal.

The air fuel ratio sensor is used as both a control sensor and monitoring sensor in diesel engines. The lambda air fuel ratio sensor is necessary to ensure the value of the exhaust gas is within compliance. The air fuel ratio sensor is necessary for calculating the average amount value for the injectors. The lambda air fuel ratio sensor measures the air fuel ratio. If there is a deviation, the ECM changes the exhaust gas recirculation rate to optimize the air fuel ratio. Adjusting the average amount value is not a control operation which is performed. air fuel ratio sensor deviation is "learned" to the characteristic map and stored temporarily by the ECM.

The sensor system of the broadband air fuel ratio sensor is composed of several thin layers of zirconium dioxide ceramic. The heating element within the laminate ensures the required operating temperature of at least 760°C. The broadband air fuel ratio sensor includes two cells, a measurement cell and a reference cell. These two cells are coated in electrodes made of platinum.

Tip:

  • Although the DTC titles say HO2S heater, these DTCs relate to the air fuel ratio sensor heater.

  • Sensor 1 is the sensor installed in the exhaust manifold converter in the front of the catalytic converter.

  • Sensor 2 is the sensor installed in the exhaust manifold converter in the rear of the catalytic converter.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0030

HO2S Heater Control Circuit Bank 1 Sensor 1

Ground short in air fuel ratio sensor (for sensor 1) heater circuit for 2 seconds.

(3 trip detection logic)

  • Short in air fuel ratio sensor (for sensor 1) heater circuit

  • Air fuel ratio sensor (for sensor 1)

  • ECM

Does not come on

DTC stored

WIRING DIAGRAM

A351167E03

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.

Tip:

  • When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. 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 GTS display.

  • 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, and other data from the time the malfunction occurred.

PROCEDURE

  1. INSPECT AIR FUEL RATIO SENSOR ((FOR SENSOR 1) (HEATER RESISTANCE))

    1. Inspect the air fuel ratio sensor (for sensor 1).

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE AIR FUEL RATIO SENSOR (FOR SENSOR 1)Click here

    OK

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

    1. Disconnect the air fuel ratio sensor (for sensor 1) 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

      B107-1 (AF1+) - B112-127 (AF1+)

      Always

      Below 1 Ω

      B107-2 (AF1-) - B112-126 (AF1-)

      Always

      Below 1 Ω

      B107-3 (HAF1) - B112-46 (HAF1)

      Always

      Below 1 Ω

      B107-5 (TR1) - B112-128 (TR1)

      Always

      Below 1 Ω

      B107-6 (RE1) - B112-125 (RE1)

      Always

      Below 1 Ω

      B107-1 (AF1+) or B112-127 (AF1+) - Body ground

      Always

      10 kΩ or higher

      B107-2 (AF1-) or B112-126 (AF1-) - Body ground

      Always

      10 kΩ or higher

      B107-3 (HAF1) or B112-46 (HAF1) - Body ground

      Always

      10 kΩ or higher

      B107-5 (TR1) or B112-128 (TR1) - Body ground

      Always

      10 kΩ or higher

      B107-6 (RE1) or B112-125 (RE1) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTORClick here

    OK

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE)

    A351154C11

    *a

    Front view of wire harness connector

    (to Air Fuel Ratio Sensor (for Sensor 1))

    1. Disconnect the air fuel ratio sensor (for sensor 1) connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      B107-4 (+B) - Body ground

      Ignition switch ON

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR (FOR SENSOR 1) - EFI MAIN NO. 1 RELAY)Click here

    OK

  4. REPLACE ECM

    1. Replace the ECM.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  5. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR (FOR SENSOR 1) - EFI MAIN NO. 1 RELAY)

    1. Disconnect the air fuel ratio sensor (for sensor 1) connector.

    2. Remove the EFI MAIN NO. 1 relay from the engine room and junction block.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B107-4 (+B) - 3 (EFI MAIN NO. 1 relay holder)

      Always

      Below 1 Ω

      B107-4 (+B) or 3 (EFI MAIN NO. 1 relay holder) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTORClick here

    OK

  6. CHECK ECM POWER SOURCE CIRCUIT

    1. Check the ECM power source circuit.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  7. REPAIR OR REPLACE HARNESS OR CONNECTOR

    1. Repair or replace the harness or connector.

    Result

    Proceed to

    NEXT
    NEXT

  8. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    1. Connect the GTS to the DLC3.

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

    3. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    4. Turn the ignition switch off and wait for 60 seconds or more [A].

    5. Perform road test [B].

    6. Repeat [A] and [B] for the number of trips detected.

    7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

      Powertrain > Engine and ECT > Trouble Codes

    8. Confirm that the DTC is not output again.

    Result

    Proceed to

    NEXT
    NEXT

    END

  9. REPLACE AIR FUEL RATIO SENSOR (FOR SENSOR 1)

    1. Replace the air fuel ratio sensor (for sensor 1).

      Click here

    2. Perform the O2 sensor learning value reset.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here