SFI SYSTEM, 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

Refer to DTC P0031 Click here.

DTC No. DTC Detection Condition Trouble Area

P2237

P2240

Open in the circuit between terminals A1A+ (A2A+) and A1A- (A2A-) of the air fuel ratio sensor while engine is running

(2 trip detection logic)

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • ECM

P2238

P2241

Any of the following conditions are met

(2 trip detection logic)


  • Air fuel ratio sensor output drops while engine is running.


  • Voltage at terminal A1A+ (A2A+) is 0.5 V or less.


  • Voltage difference between terminals A1A+ (A2A+) and A1A- (A2A-) is 0.1 V or less.

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • ECM

P2239

P2242

A1A+ (A2A+) voltage more than 4.5 V

(2 trip detection logic)

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • ECM

P2252

P2255

A1A- (A2A-) voltage 0.5 V or less

(2 trip detection logic)

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • ECM

P2253

P2256

A1A- (A2A-) voltage more than 4.5 V

(2 trip detection logic)

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • ECM

MONITOR DESCRIPTION

These DTCs are output when there is an open or short in the air fuel ratio sensor circuit, or if air fuel ratio sensor output drops. To detect these problems, the voltage of the air fuel ratio sensor is monitored when turning the engine switch to the on (IG) position, and the admittance (admittance is an electrical term that indicates the ease of flow of current) is checked while driving. If the voltage of the air fuel ratio sensor is between 0.6 V and 4.5 V, it is considered normal. If the voltage is out of the specified range, or the admittance is less than the standard value, the ECM will determine that there is a malfunction in the air fuel ratio sensor. If the same malfunction is detected in next driving cycle, the MIL will be illuminated and a DTC will be stored.

WIRING DIAGRAM

Refer to DTC P2195 Click here.

INSPECTION PROCEDURE

Note

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

Tech Tips

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, if the air-fuel ratio was lean or rich, 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 connectors.

    2. Disconnect the ECM connectors.

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

      Standard resistance (Check for open)
      Tester Connection Condition Specified Condition
      E42-1 ( HA1A) - E6-5 (HA1A) Always Below 1 Ω
      E42-3 (A1A+) - E5-23 (A1A+) Always Below 1 Ω
      E42-4 (A1A-) - E5-22 (A1A-) Always Below 1 Ω
      E38-1 (HA2A) - E6-6 (HA2A) Always Below 1 Ω
      E38-3 (A2A+) - E5-21 (A2A+) Always Below 1 Ω
      E38-4 (A2A-) - E5-20 (A2A-) Always Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Condition Specified Condition
      E42-1 ( HA1A) or E6-5 (HA1A) - Body ground Always 10 kΩ or higher
      E42-3 (A1A+) or E5-23 (A1A+) - Body ground Always 10 kΩ or higher
      E42-4 (A1A-) or E5-22 (A1A-) - Body ground Always 10 kΩ or higher
      E38-1 (HA2A) or E6-6 (HA2A) -Body ground Always 10 kΩ or higher
      E38-3 (A2A+) or E5-21 (A2A+) - Body ground Always 10 kΩ or higher
      E38-4 (A2A-) or E5-20 (A2A-) - Body ground Always 10 kΩ or higher

    4. Reconnect the air fuel ratio sensor connectors.

    5. Reconnect the ECM connectors.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air-fuel ratio sensor Click here.


    NEXT

  3. CHECK WHETHER DTC OUTPUT RECURS


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG) and turn the tester ON.

    3. Clear the DTCs Click here.

    4. Start the engine.

    5. Allow the engine to idle for 5 minutes or more.

    6. Enter the following menus: Powertrain / Engine / DTC / Pending.

    7. Read pending DTCs.

      Result
      Display (DTC Output) Proceed to
      No output A
      P2237, P2240, P2238, P2241, P2239, P2242, P2252, P2255, P2253 or P2256 B

    B

    REPLACE ECM Click here

    A

    END