ECD SYSTEM, Diagnostic DTC:P2243 and P2251

DTC Code DTC Name
P2243 O2 Sensor Reference Voltage Circuit / Open Bank 1 Sensor 1
P2251 O2 Sensor Negative Current Control Circuit / Open Bank 1 Sensor 1

DESCRIPTION

Refer to DTC P0030.

Click here

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P2243

O2 Sensor Reference Voltage Circuit / Open Bank 1 Sensor 1

Open in air fuel ratio sensor (for sensor 1) circuit for 0.5 seconds.

(3 trip detection logic)

  • Open or short in air fuel ratio sensor (for sensor 1) circuit

  • Air fuel ratio sensor (for sensor 1)

  • Open or short in air fuel ratio sensor (for sensor 1) heater circuit

  • ECM

Does not come on

DTC stored

P2251

O2 Sensor Negative Current Control Circuit / Open Bank 1 Sensor 1

Air fuel ratio sensor (for sensor 1) circuit output voltage is 3 V or more for 0.5 seconds.

(3 trip detection logic)

  • Open or short in air fuel ratio sensor (for sensor 1) circuit

  • Air fuel ratio sensor (for sensor 1)

  • Open or short in air fuel ratio sensor (for sensor 1) heater circuit

  • ECM

Does not come on

DTC stored

WIRING DIAGRAM

Refer to DTC P0030.

Click here

CAUTION / NOTICE / HINT

Note:

When replacing the ECM and/or air fuel ratio sensor, the ECM needs registration and initialization.

Click here

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. 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

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE)

    A351154C15

    *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

  3. 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

  4. REPLACE ECM

    1. Replace the ECM.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  5. 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

  6. 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 relay block 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

  7. 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

  8. REPAIR OR REPLACE HARNESS OR CONNECTOR

    1. Repair or replace the harness or connector.

    Result

    Proceed to

    NEXT
    NEXT

  9. 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