SFI SYSTEM, Diagnostic DTC:P0037, P0038, P0057, P0058

DTC Code DTC Name
P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)
P0038 Oxygen Sensor Heater Control Circuit High (Bank 1 Sensor 2)
P0057 Oxygen Sensor Heater Control Circuit Low (Bank 2 Sensor 2)
P0058 Oxygen Sensor Heater Control Circuit High (Bank 2 Sensor 2)

DESCRIPTION

Refer to DTC P0136 Click here.

Tech Tips


  • Sensor 2 refers to the sensor mounted behind the three-way catalytic converter and located furthest from the engine assembly.

  • When any of these DTCs are set, the ECM enters fail-safe mode. The ECM turns off the heated oxygen sensor heater in fail-safe mode. Fail-safe mode continues until the ignition switch is turned off.

  • The ECM provides a pulse width modulated control circuit to adjust the current through the heater. The heated oxygen sensor heater circuit uses a relay on the B+ side of the circuit.

A017DXME71
DTC No. DTC Detection Condition Trouble Area

P0037

P0057

Heated oxygen sensor heater current is less than 0.3 A (1 trip detection logic)
  • Open in heated oxygen sensor heater circuit

  • Heated oxygen sensor heater

  • EFI MAIN relay

  • ECM

P0038

P0058

Heated oxygen sensor heater current is more than 2 A (1 trip detection logic)
  • Short in heated oxygen sensor heater circuit

  • Heated oxygen sensor heater

  • EFI MAIN relay

  • ECM

Tech Tips


  • Bank 1 refers to the bank that includes cylinder No. 1.

  • Bank 2 refers to the bank that does not include cylinder No. 1.

  • Sensor 1 refers to the sensor closest to the engine assembly.

  • Sensor 2 refers to the sensor furthest away from the engine assembly.

WIRING DIAGRAM

Refer to DTC P0136 Click here

INSPECTION PROCEDURE

Tech Tips


  • If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.

  • Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE


  1. INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)


    1. A017CL3E06

      Disconnect the heated oxygen sensor connector.

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

      Standard resistance
      Bank 1
      Tester Connection Condition Specified Condition
      2 (HT1B) - 1 (+B) 20°C (68°F) 11 to 16 Ω
      2 (HT1B) - 3 (E2) Always 10 kΩ or higher
      Bank 2
      Tester Connection Condition Specified Condition
      1 (HT2B) - 2 (+B) 20°C (68°F) 11 to 16 Ω
      1 (HT2B) - 4 (E2) Always 10 kΩ or higher
    3. Reconnect the heated oxygen sensor connector.


    NG
    OK
  2. INSPECT TERMINAL VOLTAGE (HEATER POWER SOURCE)


    1. A017CNVE03

      Turn the ignition switch on (IG).

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

      Standard voltage
      Bank 1
      Tester Connection Switch Condition Specified Condition
      P1-1 (+B) - Body ground Ignition switch on (IG) 9 to 14 V
      Bank 2
      Tester Connection Switch Condition Specified Condition
      B38-2 (+B) - Body ground Ignition switch on (IG) 9 to 14 V

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)


    1. A017FT5E02

      Disconnect the heated oxygen sensor connector.

    2. Disconnect the ECM connector.

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

      Standard resistance (Check for open)
      Bank 1
      Tester Connection Condition Specified Condition
      P1-2 (HT1B) - B1-1 (HT1B) Always Below 1 Ω
      Bank 2
      Tester Connection Condition Specified Condition
      B38-1 (HT2B) - B2-5 (HT2B) Always Below 1 Ω
      Standard resistance (Check for short)
      Bank 1
      Tester Connection Condition Specified Condition
      P1-2 (HT1B) or B1-1 (HT1B) - Body ground Always Below 1 Ω
      Bank 2
      Tester Connection Condition Specified Condition
      B38-1 (HT2B) or B2-5 (HT2B) - Body ground Always Below 1 Ω
    4. Reconnect the heated oxygen sensor connector.

    5. Reconnect the ECM connector.


    NG
    OK
  4. INSPECT FUSE (EFI NO. 3 FUSE)


    1. A017ENJE02

      Remove the EFI No. 3 fuse from engine room relay block.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      EFI No. 3 fuse Always Below 1 Ω
    3. Reinstall the EFI No. 3 fuse.


    NG
    OK