Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

Engine. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35
3Zr-Fae Engine Control System. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)

CHECK HEATED OXYGEN SENSOR (POWER SOURCE)

CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)

CHECK WHETHER DTC OUTPUT RECURS (DTC P0037, P0038, P102D)

CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - INTEGRATION RELAY (EFI MAIN))

DTC P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

DTC P0038 Oxygen Sensor Heater Control Circuit High (Bank 1 Sensor 2)

DTC P102D O2 Sensor Heater Circuit Performance Bank 1 Sensor 2 Stuck ON


DESCRIPTION

  1. Refer to DTC P0136 (RAV4_ACA30 RM000000WBY0G1X_01.html).

HINT:
  1. Sensor 2 refers to the sensor mounted behind the three way catalytic converter and located far from the engine assembly.

  2. 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. Fail-safe mode continues until the ignition switch is turned off.


    Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.3Zr-Fae Engine Control System.Sfi System. Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)


DTC No.
DTC Detection Condition
Trouble Area
P0037
The heated oxygen sensor heater current is below 0.3 A when the heater operates with +B higher than 10.5 V (1 trip detection logic).
  1. Open in heated oxygen sensor heater circuit
  2. Heated oxygen sensor heater (sensor 2)
  3. Integration relay (EFI MAIN relay)
  4. ECM
P0038
The heated oxygen sensor heater current exceeds 2 A when the heater operates (1 trip detection logic).
  1. Short in heated oxygen sensor heater circuit
  2. Heated oxygen sensor heater (sensor 2)
  3. Integration relay (EFI MAIN relay)
  4. ECM
P102D
The heater current is higher than the specified value while the heater is not operating (1 trip detection logic).
ECM

WIRING DIAGRAM

Refer to DTC P2195 (RAV4_ACA30 RM000000WC40NNX_07.html).

INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
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 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.
1.INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)


    Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.3Zr-Fae Engine Control System.Sfi System. Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

  1. Disconnect the heated oxygen sensor connector.

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

    Standard Resistance:
    for LHD
    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
    for RHD
    Tester Connection
    		Condition
    		Specified Condition
    1 (HT1B) - 2 (+B)
    		20°C (68°F)
    		11 to 16 Ω
    1 (HT1B) - 4 (E2)
    		Always
    		10 kΩ or higher

  1. Reconnect the heated oxygen sensor connector.



NG
REPLACE HEATED OXYGEN SENSOR (RAV4_ACA30 RM000001ROP00TX.html)
OK


2.CHECK HEATED OXYGEN SENSOR (POWER SOURCE)


    Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.3Zr-Fae Engine Control System.Sfi System. Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

  1. Disconnect the heated oxygen sensor connector.

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

    Standard Voltage (for LHD):
    for LHD
    Tester Connection
    		Switch Condition
    		Specified Condition
    E105-1 (+B) - Body ground
    		Ignition switch ON
    		11 to 14 V
    for RHD
    Tester Connection
    		Switch Condition
    		Specified Condition
    E94-2 (+B) - Body ground
    		Ignition switch ON
    		11 to 14 V

  1. Reconnect the heated oxygen sensor connector.



NG
Go to step 5
OK


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


    Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.3Zr-Fae Engine Control System.Sfi System. Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

  1. Disconnect the heated oxygen sensor connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):
    for LHD
    Tester Connection
    		Condition
    		Specified Condition
    E105-2 (HT1B) - B32-63 (HT1B)
    		Always
    		Below 1 Ω
    for RHD
    Tester Connection
    		Switch Condition
    		Specified Condition
    E94-1 (HT1B) - B32-63 (HT1B)
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    for LHD
    Tester Connection
    		Condition
    		Specified Condition
    E105-2 (HT1B) or B32-63 (HT1B) - Body ground
    		Always
    		10 kΩ or higher
    for RHD
    Tester Connection
    		Switch Condition
    		Specified Condition
    E94-1 (HT1B) - B32-63 (HT1B)
    		Always
    		10 kΩ or higher

  1. Reconnect the heated oxygen sensor connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (HEATED OXYGEN SENSOR - ECM)
OK


4.CHECK WHETHER DTC OUTPUT RECURS (DTC P0037, P0038, P102D)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the tester on.

  1. Clear the DTCs (RAV4_ACA30 RM000000PDK0WCX.html).

  1. Start the engine.

  1. Allow the engine to idle for 1 minute or more.

  1. Enter the following menus: Powertrain / Engine and ECT / DTC.

  1. Read the DTCs.

    Result
    Result
    		Proceed to
    DTC is not output
    		A
    DTC P0037, P0038 or P102D is output
    		B


B
REPLACE ECM (RAV4_ACA30 RM0000017UO01KX.html)
A

CHECK FOR INTERMITTENT PROBLEMS (RAV4_ACA30 RM000000PDQ0T1X.html)

5.CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - INTEGRATION RELAY (EFI MAIN))


    Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.3Zr-Fae Engine Control System.Sfi System. Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

  1. Disconnect the heated oxygen sensor connector.

  1. Remove the integration relay (EFI MAIN relay) from the engine room No. 1 relay block.

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

    Standard Resistance (Check for Open):
    for LHD
    Tester Connection
    		Condition
    		Specified Condition
    E105-1 (+B) - 1A-4
    		Always
    		Below 1 Ω
    for RHD
    Tester Connection
    		Switch Condition
    		Specified Condition
    E94-2 (+B) - 1A-4
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    for LHD
    Tester Connection
    		Condition
    		Specified Condition
    E105-1 (+B) or 1A-4 - Body ground
    		Always
    		10 kΩ or higher
    for RHD
    Tester Connection
    		Switch Condition
    		Specified Condition
    E94-2 (+B) or 1A-4 - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the heated oxygen sensor connector.

  1. Reinstall the integration relay.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (HEATED OXYGEN SENSOR - INTEGRATION RELAY (EFI MAIN))
OK

GO TO ECM POWER SOURCE CIRCUIT (RAV4_ACA30 RM00000276902PX.html)