SFI SYSTEM, Diagnostic DTC:P0037, P0038, P0057, P0058, P102D, P105D

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)
P102D O2 Sensor Heater Circuit Performance Bank 1 Sensor 2 Stuck ON
P105D O2 Sensor Heater Circuit Performance Bank 2 Sensor 2 Stuck ON

DESCRIPTION

Refer to DTC P0136 Click here.

Tech Tips


  • Sensor 2 refers to the sensor mounted behind the Three-Way Catalytic Converter (TWC) and located far from the engine assembly.

  • When any of these DTCs are stored, the ECM enters fail-safe mode. The ECM turns off the heated oxygen sensor heater in fail-safe mode. The ECM continues operating in fail-safe mode 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.

    A00OB4JE12
DTC No. DTC Detection Condition Trouble Area

P0037

P0057

 The heated oxygen sensor heater (bank 1, 2 sensor 2) current is below 0.3 A (1 trip detection logic).

  • Open in heated oxygen sensor heater (bank 1, 2 sensor 2) circuit

  • Heated oxygen sensor heater (bank 1, 2 sensor 2)

  • EFI No. 2 fuse

  • ECM

P0038

P0058

 The heated oxygen sensor (bank 1, 2 sensor 2) current is higher than 2 A (1 trip detection logic).

  • Short in heated oxygen sensor (bank 1, 2 sensor 2) circuit

  • Heated oxygen sensor heater (bank 1, 2 sensor 2)

  • EFI No. 2 fuse

  • ECM

P102D

P105D

 The heated oxygen sensor heater (bank 1, 2 sensor 2) current is higher than a specified value while the heater is not operating (1 trip detection logic). ECM

Tech Tips


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

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

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

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

MONITOR DESCRIPTION

The sensing portion of the heated oxygen sensor has a zirconia element which is used to detect the oxygen concentration in the exhaust gas. If the zirconia element is at the appropriate temperature and the difference between the oxygen concentrations surrounding the inside and outside surfaces of the sensor is large, the zirconia element generates voltage signals. In order to increase the oxygen concentration detecting capacity of the zirconia element, the ECM supplements the heat from the exhaust with heat from a heating element inside the sensor.

The ECM monitors the current applied to the heated oxygen sensor heater to check the heater for malfunctions. If the heater current is outside the normal range, the signal transmitted by the heated oxygen sensor becomes inaccurate. When the current in the heated oxygen sensor heater is outside the normal operating range, the ECM interprets this as a malfunction in the sensor and stores a DTC.

WIRING DIAGRAM

Refer to DTC P0136 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. INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)


    1. Inspect the heated oxygen sensor Click here.


    NG

    REPLACE HEATED OXYGEN SENSOR Click here

    OK

  2. CHECK TERMINAL VOLTAGE (+B OF HEATED OXYGEN SENSOR)

    A00O8JRE03
    Text in Illustration
    *a

    Front view of wire harness connector

    (to Heated Oxygen Sensor Bank 1)
    *b

    Front view of wire harness connector

    (to Heated Oxygen Sensor Bank 2)

    1. Disconnect the heated oxygen sensor connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      C27-2 (+B) - Body ground Ignition switch ON 11 to 14 V
      C28-2 (+B) - Body ground Ignition switch ON 11 to 14 V

    3. Reconnect the heated oxygen sensor connector.


    NG

    CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - NO. 1 INTEGRATION RELAY) Click here

    OK

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


    1. 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)
      Tester Connection Condition Specified Condition
      C27-1 (HT1B) - C37-12 (HT1B) Always Below 1 Ω
      C28-1 (HT2B) - C37-13 (HT2B) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      C27-1 (HT1B) or C37-12 (HT1B) - Body ground Always 10 kΩ or higher
      C28-1 (HT2B) or C37-13 (HT2B) - Body ground Always 10 kΩ or higher

    4. Reconnect the ECM connector.

    5. Reconnect the heated oxygen sensor connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ECM Click here

  4. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - NO. 1 INTEGRATION RELAY)


    1. Disconnect the heated oxygen sensor connector.

    2. Remove the No. 1 integration relay from the engine room relay block.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      C27-2 (+B) - 1B-4 Always Below 1 Ω
      C28-2 (+B) - 1B-4 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      C27-2 (+B) or 1B-4 - Body ground Always 10 kΩ or higher
      C28-2 (+B) or 1B-4 - Body ground Always 10 kΩ or higher

    4. Reinstall the No. 1 integration relay.

    5. Reconnect the heated oxygen sensor connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    CHECK ECM POWER SOURCE CIRCUIT Click here