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DTC P0A1A-200, P0A1A-792, P0A1A-793: Generator Control Module; Generator Control Module; Generator Control Module: Procedure

  1. CHECK DTC OUTPUT (HV) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Enter the following menus: Powertrain/Hybrid Control/Trouble Codes.
    4. Check if DTCs are output.

      Result

      Result Proceed to
      P0A1A-200, 792, or 793 only is output. A
      Any of the following DTCs are also output. B
      DTC No. Relevant Diagnosis
      P0A3F-243 Drive Motor "A" Position Sensor Circuit
      P0A4B-253 Generator Position Sensor Circuit
      P0A4C-513 Generator Position Sensor Circuit Range/Performance
      P0A4D-255 Generator Position Sensor Circuit Low
    5. Turn the power switch off.

    B → See step   13 

    A: Go to next step 

  2. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR) 
    WARNING: Be sure to wear insulated gloves.
    1. Check that the service plug grip is not installed.
      NOTE: After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
      NOTE: Before disconnecting the connector, confirm that it is properly connected by checking that the locking claws are engaged and that the connector does not pull out.
      Fig 1: Identifying Inverter With Converter Assembly Low Voltage Connector
      GTY280842Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the connection of the low voltage connector of the inverter with converter assembly.

      OK

      The connector is connected securely and there are no contact problems.

      HINT: 

      When connecting the connector, insert it with the locking lever in the raised position. Rotate the lever downward and make sure that the connector is pulled into its socket. When the locking lever is in its fully closed position, a click will be heard as its locking claws engage. After the click is heard, pull up on the connector to confirm that it is properly connected.

    NG → CONNECT SECURELY 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - GENERATOR RESOLVER) 
    WARNING: Be sure to wear insulated gloves.
    1. Disconnect the low voltage connector C22 from the inverter with converter assembly.
    2. Turn the power switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.
      Fig 2: Identifying Low Voltage Connector C22 From Inverter With Converter Assembly
      GTY257119Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      C22-6 (GRF) - Body ground Power switch on (IG) Below 1 V
      C22-5 (GRFG) - Body ground Power switch on (IG) Below 1 V
      C22-1 (GSN) - Body ground Power switch on (IG) Below 1 V
      C22-2 (GSNG) - Body ground Power switch on (IG) Below 1 V
      C22-3 (GCS) - Body ground Power switch on (IG) Below 1 V
      C22-4 (GCSG) - Body ground Power switch on (IG) Below 1 V
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Inverter with Converter Assembly)
      NOTE: Turning the power switch on (IG) with the low voltage connector of the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.
    4. Turn the power switch off.
    5. Connect the low voltage connector to the inverter with converter assembly.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK GENERATOR RESOLVER 
    1. Disconnect the low voltage connector C22 from the inverter with converter assembly.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 3: Identifying Low Voltage Connector C22 From Inverter With Converter Assembly
      GTY257119Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      C22-6 (GRF) - C22-5 (GRFG) Power switch off 4.2 to 12.5 Ω
      C22-1 (GSN) - C22-2 (GSNG) Power switch off 9.8 to 20.1 Ω
      C22-3 (GCS) - C22-4 (GCSG) Power switch off 9.8 to 20.1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      C22-6 (GRF) or C22-5 (GRFG) - Body ground and other terminals Power switch off 10 kΩ or higher
      C22-1 (GSN) or C22-2 (GSNG) - Body ground and other terminals Power switch off 10 kΩ or higher
      C22-3 (GCS) or C22-4 (GCSG) - Body ground and other terminals Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Inverter with Converter Assembly)
    3. Connect the inverter with converter assembly connector.

    NG → See step   9 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - MOTOR RESOLVER) 
    WARNING: Be sure to wear insulated gloves.
    1. Disconnect the low voltage connector C22 from the inverter with converter assembly.
    2. Turn the power switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.
      Fig 4: Identifying Low Voltage Connector C22 From Inverter With Converter Assembly
      GTY257118Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      C22-13 (MRF) - Body ground Power switch on (IG) Below 1 V
      C22-12 (MRFG) - Body ground Power switch on (IG) Below 1 V
      C22-11 (MSN) - Body ground Power switch on (IG) Below 1 V
      C22-7 (MSNG) - Body ground Power switch on (IG) Below 1 V
      C22-8 (MCS) - Body ground Power switch on (IG) Below 1 V
      C22-9 (MCSG) - Body ground Power switch on (IG) Below 1 V
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Inverter with Converter Assembly)
      NOTE: Turning the power switch on (IG) with the low voltage connector of the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.
    4. Turn the power switch off.
    5. Connect the inverter with converter assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. CHECK MOTOR RESOLVER 
    1. Disconnect the low voltage connector C22 from the inverter with converter assembly.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 5: Identifying Low Voltage Connector C22 From Inverter With Converter Assembly
      GTY257118Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      C22-13 (MRF) - C22-12 (MRFG) Power switch off 4.2 to 12.5 Ω
      C22-11 (MSN) - C22-7 (MSNG) Power switch off 9.8 to 20.1 Ω
      C22-8 (MCS) - C22-9 (MCSG) Power switch off 9.8 to 20.1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      C22-13 (MRF) or C22-12 (MRFG) - Body ground and other terminals Power switch off 10 kΩ or higher
      C22-11 (MSN) or C22-7 (MSNG) - Body ground and other terminals Power switch off 10 kΩ or higher
      C22-8 (MCS) or C22-9 (MCSG) - Body ground and other terminals Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Inverter with Converter Assembly)
    3. Connect the inverter with converter assembly connector.

    NG → See step   11 

    OK: Go to next step 

  7. CHECK CONNECTOR CONNECTION CONDITION (GENERATOR RESOLVER CONNECTOR) 
    1. Check the connection of the generator resolver connector.

      OK

      The connector is connected securely and there are no contact problems.

      Fig 6: Checking Connection Of C23 Generator Resolver Connector
      GTY256724Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG → CONNECT SECURELY 

    OK: Go to next step 

  8. CHECK CONNECTOR CONNECTION CONDITION (MOTOR RESOLVER CONNECTOR) 
    1. Check the connection of the motor resolver connector.

      OK

      The connector is connected securely and there are no contact problems.

      Fig 7: Checking Connection Of Motor Resolver Connector
      GTY282101Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG → CONNECT SECURELY 

    OK → See step   14 

  9. CHECK CONNECTOR CONNECTION CONDITION (GENERATOR RESOLVER CONNECTOR) 
    1. Check the connection of the generator resolver connector.

      OK

      The connector is connected securely and there are no contact problems.

      Fig 8: Checking Connection Of C23 Generator Resolver Connector
      GTY256724Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG → CONNECT SECURELY 

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - GENERATOR RESOLVER) 
    1. Disconnect the low voltage connector C22 from the inverter with converter assembly.
    2. Disconnect connector C23 from the generator resolver.
      Fig 9: Identifying C22 From Inverter With Converter Assembly & C23 Generator Resolver Connectors
      GTY264754Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      C23-1 (GRF) - C22-6 (GRF) Power switch off Below 1 Ω
      C23-6 (GRFG) - C22-5 (GRFG) Power switch off Below 1 Ω
      C23-2 (GSN) - C22-1 (GSN) Power switch off Below 1 Ω
      C23-7 (GSNG) - C22-2 (GSNG) Power switch off Below 1 Ω
      C23-3 (GCS) - C22-3 (GCS) Power switch off Below 1 Ω
      C23-8 (GCSG) - C22-4 (GCSG) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      C23-1 (GRF) or C22-6 (GRF) - Body ground and other terminals Power switch off 10 kΩ or higher
      C23-6 (GRFG) or C22-5 (GRFG) - Body ground and other terminals Power switch off 10 kΩ or higher
      C23-2 (GSN) or C22-1 (GSN) - Body ground and other terminals Power switch off 10 kΩ or higher
      C23-7 (GSNG) or C22-2 (GSNG) - Body ground and other terminals Power switch off 10 kΩ or higher
      C23-3 (GCS) or C22-3 (GCS) - Body ground and other terminals Power switch off 10 kΩ or higher
      C23-8 (GCSG) or C22-4 (GCSG) - Body ground and other terminals Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Generator Resolver)
      *2 Front view of wire harness connector
      (to Inverter with Converter Assembly)

      HINT: 

      The generator resolver is not available separately. If it requires replacement, replace the hybrid vehicle transaxle assembly.

    4. Connect the generator resolver connector.
    5. Connect the inverter with converter assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   15 

  11. CHECK CONNECTOR CONNECTION CONDITION (MOTOR RESOLVER CONNECTOR) 
    1. Check the connection of the motor resolver connector.

      OK

      The connector is connected securely and there are no contact problems.

      Fig 10: Checking Connection Of Motor Resolver Connector
      GTY282101Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG → CONNECT SECURELY 

    OK: Go to next step 

  12. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - MOTOR RESOLVER) 
    1. Disconnect the low voltage connector C22 from the inverter with converter assembly.
    2. Disconnect connector C24 from the motor resolver.
      Fig 11: Checking Harness And Connector (Inverter With Converter Assembly - Motor Resolver)
      GTY277893Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      C24-1 (MRF) - C22-13 (MRF) Power switch off Below 1 Ω
      C24-4 (MRFG) - C22-12 (MRFG) Power switch off Below 1 Ω
      C24-2 (MSN) - C22-11 (MSN) Power switch off Below 1 Ω
      C24-5 (MSNG) - C22-7 (MSNG) Power switch off Below 1 Ω
      C24-3 (MCS) - C22-8 (MCS) Power switch off Below 1 Ω
      C24-6 (MCSG) - C22-9 (MCSG) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      C24-1 (MRF) or C22-13 (MRF) - Body ground and other terminals Power switch off 10 kΩ or higher
      C24-4 (MRFG) or C22-12 (MRFG) - Body ground and other terminals Power switch off 10 kΩ or higher
      C24-2 (MSN) or C22-11 (MSN) - Body ground and other terminals Power switch off 10 kΩ or higher
      C24-5 (MSNG) or C22-7 (MSNG) - Body ground and other terminals Power switch off 10 kΩ or higher
      C24-3 (MCS) or C22-8 (MCS) - Body ground and other terminals Power switch off 10 kΩ or higher
      C24-6 (MCSG) or C22-9 (MCSG) - Body ground and other terminals Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Motor Resolver)
      *2 Front view of wire harness connector
      (to Inverter with Converter Assembly)

      HINT: 

      The motor resolver is not available separately. If it requires replacement, replace the hybrid vehicle transaxle assembly.

    4. Connect the motor resolver connector.
    5. Connect the inverter with converter assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   15 

  13. GO TO DTC TABLE. Refer to  DIAGNOSTIC TROUBLE CODE TABLE 
  14. REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to  COMPONENTS 
  15. REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY. Refer to  COMPONENTS 
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