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DTC P0C2B-15: Auxiliary Transmission Fluid Pump Control Module Feedback Signal Circuit Short to Battery or Open [12/2021 - 10/2023]: Procedure

  1. PERFORM ACTIVE TEST USING GTS (OIL PUMP) 

    Pre-procedure1

    • Drive the vehicle to warm up the engine and automatic transmission fluid.

      HINT: 

      The oil pump with motor assembly may not operate properly if the automatic transmission fluid temperature is low. Make sure to warm up the automatic transmission fluid before performing the Active Test. (automatic transmission fluid temperature: 25°C (77°F) or higher)

    • Connect the GTS to the DLC3.
    • Turn the ignition switch to ON.

      HINT: 

      Do not start the engine.

    • Turn the GTS on.
    • Enter the following menus: Powertrain / Stop and Start / Active Test / Oil Pump.

      Powertrain > Stop and Start > Active Test 

      Tester Display
      Oil Pump
    • Check the operating sound of the oil pump with motor assembly while performing the Active Test.

      Standard

      Oil Pump Result
      ON Operating sound can be heard
      OFF Operating sound cannot be heard

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  2

  2. CHECK ENGINE STOP AND START ECU (NOPM TERMINAL WAVEFORM) 

    Pre-procedure1

    GTY1074640Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Engine Stop and Start ECU)    		 - -
    • Connect an oscilloscope to terminals NOPM and DGND of the engine stop and start ECU connector.
    • Enter the following menus: Powertrain / Stop and Start / Active Test / Oil Pump.

      HINT: 

      Do not start the engine.

      Powertrain > Stop and Start > Active Test 

      Tester Display
      Oil Pump
    • Check the waveform while performing the Active Test.
      Item Condition
      Tester Connection B38-27 (NOPM) - B38-6 (DGND)
      Tool Setting 5 V/DIV., 5 ms./DIV.
      Condition
      • Ignition switch ON (engine is stopped)
      • Active Test "Oil Pump" being performed

      Standard

      The waveform is similar to that shown in the illustration with no noise.

      GTY1027480Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    OK 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    NG 

    See step  3

  3. CHECK OIL PUMP WITH MOTOR ASSEMBLY (OPST TERMINAL VOLTAGE) 

    Pre-procedure1

    • Disconnect the oil pump with motor assembly connector.
    • Turn the ignition switch to ON.
    • Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      C35-2 (OPST) - C35-1 (GND) Ignition switch ON 10 to 14 V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    OK 

    REPLACE OIL PUMP WITH MOTOR ASSEMBLY. Refer to  PROCEDURE - Step 10 

    Result: 

    NG 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - OIL PUMP WITH MOTOR ASSEMBLY) 

    Pre-procedure1

    • Disconnect the engine stop and start ECU connector.
    • Disconnect the oil pump with motor assembly connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B38-27 (NOPM) - C35-2 (OPST) Always Below 1 Ω
      B38-27 (NOPM) - Body ground and other terminals Always 10 kΩ or higher
      C35-2 (OPST) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    OK 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - OIL PUMP WITH MOTOR ASSEMBLY) 

    Pre-procedure1

    • Disconnect the engine stop and start ECU connector.
    • Disconnect the oil pump with motor assembly connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B37-6 (OP21) - C35-4 (+B) Always Below 1 Ω
      B37-6 (OP21) - Body ground and other terminals Always 10 kΩ or higher
      C35-4 (+B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (OIL PUMP WITH MOTOR ASSEMBLY - BODY GROUND) 

    Pre-procedure1

    • Disconnect the oil pump with motor assembly connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C35-1 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK ENGINE STOP AND START ECU (OP21 TERMINAL VOLTAGE) 

    Pre-procedure1

    GTY1074634Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Engine Stop and Start ECU)    		 - -
    • Disconnect the oil pump with motor assembly connector.
    • Enter the following menus: Powertrain / Stop and Start / Active Test / Oil Pump.

      HINT: 

      Do not start the engine.

      Powertrain > Stop and Start > Active Test 

      Tester Display
      Oil Pump
    • Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      B37-6 (OP21) - B38-6 (DGND)
      • Ignition switch ON (engine is stopped)
      • Active Test "Oil Pump" being performed
      		 10.5 to 16 V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - OIL PUMP WITH MOTOR ASSEMBLY) 

    Pre-procedure1

    • Disconnect the engine stop and start ECU connector.
    • Disconnect the oil pump with motor assembly connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B38-9 (OPM1) - C35-3 (SI) Always Below 1 Ω
      B38-9 (OPM1) - Body ground and other terminals Always 10 kΩ or higher
      C35-3 (SI) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK OIL PUMP WITH MOTOR ASSEMBLY (OPM1 TERMINAL WAVEFORM) 

    Pre-procedure1

    • Connect an oscilloscope to the OPM1 and DGND terminals of the engine stop and start ECU connector.
      GTY1074635Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Engine Stop and Start ECU)      		 - -
    • Connect the GTS to the DLC3.
    • Enter the following menus: Powertrain / Stop and Start / Active Test / Oil Pump.

      HINT: 

      Do not start the engine.

      Powertrain > Stop and Start > Active Test 

      Tester Display
      Oil Pump
    • Check the waveform while performing the Active Test.
      GTY1027497Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Item Condition
      Tester Connection B38-9 (OPM1) - B38-6 (DGND)
      Tool Setting 5 V/DIV., 5 ms./DIV.
      Condition
      • Ignition switch ON (engine is stopped)
      • Active Test "Oil Pump" being performed

      Standard

      The waveform is similar to that shown in the illustration with no noise.

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    OK 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    NG 

    REPLACE OIL PUMP WITH MOTOR ASSEMBLY. Refer to  PROCEDURE - Step 10 

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