ECD SYSTEM(w/ DPF), Diagnostic DTC:P2237, P2238, P2239, P2240, P2241, P2242, P2252, P2253, P2255, P2256

DTC Code DTC Name
P2237 Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 1 Sensor 1)
P2238 Oxygen (A/F) Sensor Pumping Current Circuit Low (Bank 1 Sensor 1)
P2239 Oxygen (A/F) Sensor Pumping Current Circuit High (Bank 1 Sensor 1)
P2240 Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 2 Sensor 1)
P2241 Oxygen (A/F) Sensor Pumping Current Circuit Low (Bank 2 Sensor 1)
P2242 Oxygen (A/F) Sensor Pumping Current Circuit High (Bank 2 Sensor 1)
P2252 Oxygen (A/F) Sensor Reference Ground Circuit Low (Bank 1 Sensor 1)
P2253 Oxygen (A/F) Sensor Reference Ground Circuit High (Bank 1 Sensor 1)
P2255 Oxygen (A/F) Sensor Reference Ground Circuit Low (Bank 2 Sensor 1)
P2256 Oxygen (A/F) Sensor Reference Ground Circuit High (Bank 2 Sensor 1)

DESCRIPTION

Tech Tips


  • For more information on the air fuel ratio sensor and Diesel Particulate Filter (DPF), refer to the following procedures Click here.

  • If P2237, P2238, P2239, P2240, P2441 or P2442 is present, refer to the DTC table for DPF system Click here.

  • These DTCs are recorded when the air fuel ratio sensor has a malfunction, although the title says oxygen sensor.

The air fuel ratio sensor has the characteristic of providing output voltage which is proportional to the air-fuel ratio. The air fuel ratio sensor output voltage* is used by the ECM to control the air-fuel ratio.

The air fuel ratio sensor is located after the DPF catalytic converter. This sensor has been developed based on the structure and technology of a sensor that is used for gasoline engines. The cover portion of the sensor has been changed for use in the diesel engine with DPF in order to eliminate the influence of the sensor temperature and particulate matter (PM).

In order to reduce PM, the ECM adjusts the air-fuel ratio to a slightly rich value (but it is lean compared with the stoichiometric air-fuel ratio) based on signals from the air fuel ratio sensor. When the ECM performs PM forced regeneration using adding fuel by the exhaust fuel addition injector, the air-fuel ratio is also properly adjusted using the sensor.

*: The voltage value changes inside the ECM only.

A01X1P4E07
P2237 (Bank 1), P2240 (Bank 2)
DTC Detection Drive Pattern DTC Detection Condition Trouble Area

  • Drive the vehicle at 50 km/h (30 mph) or more for a total of 300 seconds or more.

  • Check that "Exhaust Temperature B1S1" displays 200°C (392°F) or higher using the GTS.

When either of the following conditions is met (1 trip detection logic):


  • Air fuel ratio sensor circuit malfunction

  • The resistance of the air fuel ratio sensor element is 250 Ω or higher for 5 seconds or more.

Main trouble area: Open in air fuel ratio sensor circuit


  • Open or short in air fuel ratio sensor circuit

  • Air fuel ratio sensor

  • ECM
P2238 (Bank 1), P2241 (Bank 2)
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
Ignition switch ON for 7 seconds

Air fuel ratio sensor (for bank 1, 2) circuit low

(1 trip detection logic)

Main trouble area: Open in air fuel ratio sensor circuit


  • Open or short in air fuel ratio sensor circuit

  • Air fuel ratio sensor

  • ECM
P2239 (Bank 1), P2242 (Bank 2)
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
Ignition switch ON for 7 seconds

Air fuel ratio sensor (for bank 1, 2) circuit high

(1 trip detection logic)

Main trouble area: Short in air fuel ratio sensor circuit


  • Open or short in air fuel ratio sensor circuit

  • Air fuel ratio sensor

  • ECM
P2252 (Bank 1), P2255 (Bank 2)
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
Ignition switch ON for 7 seconds

Air fuel ratio sensor (for bank 1, 2) circuit low

(1 trip detection logic)

Main trouble area: Open in air fuel ratio sensor circuit


  • Open or short in air fuel ratio sensor circuit

  • Air fuel ratio sensor

  • ECM
P2253 (Bank 1), P2256 (Bank 2)
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
Ignition switch ON for 7 seconds

Air fuel ratio sensor (for bank 1, 2) circuit high

(1 trip detection logic)

Main trouble area: Short in air fuel ratio sensor circuit


  • Open or short in air fuel ratio sensor circuit

  • Air fuel ratio sensor

  • ECM
Related Data List
DTC No. Data List

P2237

P2238

P2239

P2252

P2253

  • AFS Voltage B1S1

  • Exhaust Temperature B1S1

P2240

P2241

P2242

P2255

P2256

  • AFS Voltage B2S1

  • Exhaust Temperature B2S1

MONITOR DESCRIPTION

The air fuel ratio sensor outputs a voltage in proportion to the air-fuel ratio. If impedance (alternating current resistance) or voltage output of the sensor deviates greatly from the standard range, the ECM interprets this as an open or short malfunction of the air fuel ratio sensor circuit.

WIRING DIAGRAM

Refer to DTC P0031 Click here.

CAUTION / NOTICE / HINT

Note


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

  • After replacing the ECM, the new ECM needs registration (See page ) and initialization Click here.

  • After replacing the fuel supply pump assembly, the ECM needs initialization Click here.

  • After replacing an injector assembly, the ECM needs registration Click here.

Tech Tips

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 - 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
      for LHD
      Tester Connection Condition Specified Condition
      C159-3 (AF1+) - C45-102 (A1A+) Always Below 1 Ω
      C159-4 (AF1-) - C45-103 (A1A-) Always Below 1 Ω
      C158-3 (AF2+) - C45-125 (A2A+) Always Below 1 Ω
      C158-4 (AF2-) - C45-126 (A2A-) Always Below 1 Ω
      C159-3 (AF1+) or C45-102 (A1A+) - Body ground Always 10 kΩ or higher
      C159-4 (AF1-) or C45-103 (A1A-) - Body ground Always 10 kΩ or higher
      C158-3 (AF2+) or C45-125 (A2A+) - Body ground Always 10 kΩ or higher
      C158-4 (AF2-) or C45-126 (A2A-) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      C159-3 (AF1+) - C46-102 (A1A+) Always Below 1 Ω
      C159-4 (AF1-) - C46-103 (A1A-) Always Below 1 Ω
      C158-3 (AF2+) - C46-125 (A2A+) Always Below 1 Ω
      C158-4 (AF2-) - C46-126 (A2A-) Always Below 1 Ω
      C159-3 (AF1+) or C46-102 (A1A+) - Body ground Always 10 kΩ or higher
      C159-4 (AF1-) or C46-103 (A1A-) - Body ground Always 10 kΩ or higher
      C158-3 (AF2+) or C46-125 (A2A+) - Body ground Always 10 kΩ or higher
      C158-4 (AF2-) or C46-126 (A2A-) - Body ground Always 10 kΩ or higher

    4. Reconnect the air fuel ratio sensor connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  2. REPLACE AIR FUEL RATIO SENSOR

    When DTC P2237, P2238, P2239, P2252 or P2253 is output:


    • Replace the air fuel ratio sensor (for bank 1) Click here.

    When DTC P2240, P2241, P2242, P2255 or P2256 is output:


    • Replace the air fuel ratio sensor (for bank 2) Click here.


    NEXT

  3. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Warm up the engine.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the GTS on.

    5. Clear the DTCs Click here.

    6. Drive the vehicle at 50 km/h (30 mph) or more for a total of 300 seconds or more.

      Tech Tips

      Make sure that the exhaust gas temperatures (Exhaust Temperature B1S1 and Exhaust Temperature B2S1) are 200°C (392°F) or higher.

    7. Confirm that the DTC is not output again.


    OK

    END

    NG

  4. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  5. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the harness or connector.


    NEXT

  6. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Warm up the engine.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the GTS on.

    5. Clear the DTCs Click here.

    6. Drive the vehicle at 50 km/h (30 mph) or more for a total of 300 seconds or more.

      Tech Tips

      Make sure that the exhaust gas temperatures (Exhaust Temperature B1S1 and Exhaust Temperature B2S1) are 200°C (392°F) or higher.

    7. Confirm that the DTC is not output again.


    NEXT

    END