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Home >> Lexus >> 2016 >> GS 450h Base >> Repair and Diagnosis (Single Page) >> Hybrid/Electric Powertrain >> Testing and Diagnosis >> Hybrid Control System (Diagnostic Codes (P0A09-591 - P0A1B-794) >> Hybrid Control System >> DTC P0A1A-200: Generator Control Module; DTC P0A1A-792: Generator Control Module; DTC P0A1A-793: Generator Control Module [09/2014 - 10/2015] >> Procedure
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DTC P0A1A-200: Generator Control Module; DTC P0A1A-792: Generator Control Module; DTC P0A1A-793: Generator Control Module [09/2014 - 10/2015]: Procedure

  1. CHECK DTC OUTPUT (HYBRID CONTROL) 
    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.

    Result:  B

    B 

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) 

    (See service information). Refer to DIAGNOSTIC TROUBLE CODE CHART [09/2014 - 10/2015] )

    Result:  A

    A 

    See step  2

  2. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR) 

    Refer to PROCEDURE - Step 4

    Result:  NG

    NG 

    CONNECT SECURELY 

    Result:  OK

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - GENERATOR RESOLVER) 
    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 service info because this may cause a malfunction.

    2. Disconnect the connector from the inverter with converter assembly.
    3. Connect the cable to the negative (-) auxiliary battery terminal.
    4. Turn the power switch on (IG).
    5. Measure the voltage according to the value(s) in the table below.
      GTY533734Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A38-20 (GRF) - Body ground Power switch on (IG) Below 1 V
      A38-9 (GRFG) - Body ground Power switch on (IG) Below 1 V
      A38-18 (GSN) - Body ground Power switch on (IG) Below 1 V
      A38-7 (GSNG) - Body ground Power switch on (IG) Below 1 V
      A38-17 (GCS) - Body ground Power switch on (IG) Below 1 V
      A38-6 (GCSG) - Body ground Power switch on (IG) Below 1 V
      TEXT IN ILLUSTRATION

      *a 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.

    6. Turn the power switch off.
    7. Disconnect the cable from the negative (-) auxiliary battery terminal.
    8. Connect the inverter with converter assembly connector.

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  4

  4. CHECK GENERATOR RESOLVER 
    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 service info because this may cause a malfunction.

    2. Disconnect the connector from the inverter with converter assembly.
    3. Measure the resistance according to the value(s) in the table below.
      GTY533734Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      A38-20 (GRF) - A38-9 (GRFG) Power switch off 4.2 to 12.5 Ω
      A38-18 (GSN) - A38-7 (GSNG) Power switch off 9.8 to 20.1 Ω
      A38-17 (GCS) - A38-6 (GCSG) Power switch off 9.8 to 20.1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      A38-20 (GRF) or A38-9 (GRFG) - Body ground and other terminals Power switch off 1 MΩ or higher
      A38-18 (GSN) or A38-7 (GSNG) - Body ground and other terminals Power switch off 1 MΩ or higher
      A38-17 (GCS) or A38-6 (GCSG) - Body ground and other terminals Power switch off 1 MΩ or higher
      TEXT IN ILLUSTRATION

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

    Result:  NG

    NG 

    See step  9

    Result:  OK

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - MOTOR RESOLVER) 
    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 service info because this may cause a malfunction.

    2. Disconnect the connector from the inverter with converter assembly.
    3. Connect the cable to the negative (-) auxiliary battery terminal.
    4. Turn the power switch on (IG).
    5. Measure the voltage according to the value(s) in the table below.
      GTY527570Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A38-40 (MRF) - Body ground Power switch on (IG) Below 1 V
      A38-29 (MRFG) - Body ground Power switch on (IG) Below 1 V
      A38-39 (MSN) - Body ground Power switch on (IG) Below 1 V
      A38-28 (MSNG) - Body ground Power switch on (IG) Below 1 V
      A38-38 (MCS) - Body ground Power switch on (IG) Below 1 V
      A38-27 (MCSG) - Body ground Power switch on (IG) Below 1 V
      TEXT IN ILLUSTRATION

      *a 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.

    6. Turn the power switch off.
    7. Disconnect the cable from the negative (-) auxiliary battery terminal.
    8. Connect the inverter with converter assembly connector.

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  6

  6. CHECK MOTOR RESOLVER 
    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 service info because this may cause a malfunction.

    2. Disconnect the connector from the inverter with converter assembly.
    3. Measure the resistance according to the value(s) in the table below.
      GTY527570Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      A38-40 (MRF) - A38-29 (MRFG) Power switch off 4.2 to 12.5 Ω
      A38-39 (MSN) - A38-28 (MSNG) Power switch off 9.8 to 20.1 Ω
      A38-38 (MCS) - A38-27 (MCSG) Power switch off 9.8 to 20.1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      A38-40 (MRF) or A38-29 (MRFG) - Body ground and other terminals Power switch off 1 MΩ or higher
      A38-39 (MSN) or A38-28 (MSNG) - Body ground and other terminals Power switch off 1 MΩ or higher
      A38-38 (MCS) or A38-27 (MCSG) - Body ground and other terminals Power switch off 1 MΩ or higher
      TEXT IN ILLUSTRATION

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

    Result:  NG

    NG 

    See step  11

    Result:  OK

    OK 

    See step  7

  7. CHECK CONNECTOR CONNECTION CONDITION (GENERATOR RESOLVER CONNECTOR) 
    1. Check the connection condition of the generator resolver connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter (See service information). Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [09/2014 - ] ).

      OK

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

      GTY529013Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:

      If the terminals connect poorly, are damaged, or contain water or foreign matter, repair or replace the wire harness or connector.

    Result:  NG

    NG 

    CONNECT SECURELY 

    Result:  OK

    OK 

    See step  8

  8. CHECK CONNECTOR CONNECTION CONDITION (MOTOR RESOLVER CONNECTOR) 
    1. Check the connection condition of the motor resolver connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter (See service information). Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [09/2014 - ] ).

      OK

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

      GTY529012Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:

      If the terminals connect poorly, are damaged, or contain water or foreign matter, repair or replace the wire harness or connector.

    Result:  OK

    OK 

    REPLACE INVERTER WITH CONVERTER ASSEMBLY 

    (See service information). Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    CONNECT SECURELY 

  9. CHECK CONNECTOR CONNECTION CONDITION (GENERATOR RESOLVER CONNECTOR) 
    1. Check the connection condition of the generator resolver connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter (See service information). Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [09/2014 - ] ).

      OK

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

      GTY529013Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:

      If the terminals connect poorly, are damaged, or contain water or foreign matter, repair or replace the wire harness or connector.

    Result:  NG

    NG 

    CONNECT SECURELY 

    Result:  OK

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - GENERATOR RESOLVER) 
    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 service info because this may cause a malfunction.

    2. Disconnect the connector from the inverter with converter assembly.
    3. Disconnect the generator resolver connector.
      GTY537158Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      F50-1 (GRF) - A38-20 (GRF) Power switch off Below 1 Ω
      F50-5 (GRFG) - A38-9 (GRFG) Power switch off Below 1 Ω
      F50-2 (GSN) - A38-18 (GSN) Power switch off Below 1 Ω
      F50-6 (GSNG) - A38-7 (GSNG) Power switch off Below 1 Ω
      F50-3 (GCS) - A38-17 (GCS) Power switch off Below 1 Ω
      F50-7 (GCSG) - A38-6 (GCSG) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      F50-1 (GRF) or A38-20 (GRF) - Body ground and other terminals Power switch off 1 MΩ or higher
      F50-5 (GRFG) or A38-9 (GRFG) - Body ground and other terminals Power switch off 1 MΩ or higher
      F50-2 (GSN) or A38-18 (GSN) - Body ground and other terminals Power switch off 1 MΩ or higher
      F50-6 (GSNG) or A38-7 (GSNG) - Body ground and other terminals Power switch off 1 MΩ or higher
      F50-3 (GCS) or A38-17 (GCS) - Body ground and other terminals Power switch off 1 MΩ or higher
      F50-7 (GCSG) or A38-6 (GCSG) - Body ground and other terminals Power switch off 1 MΩ or higher
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Generator Resolver)
      *b 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 transmission assembly.

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

    Result:  OK

    OK 

    REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY 

    (See service information). Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. CHECK CONNECTOR CONNECTION CONDITION (MOTOR RESOLVER CONNECTOR) 
    1. Check the connection condition of the motor resolver connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter (See service information). Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [09/2014 - ] ).

      OK

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

      GTY529012Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:

      If the terminals connect poorly, are damaged, or contain water or foreign matter, repair or replace the wire harness or connector.

    Result:  NG

    NG 

    CONNECT SECURELY 

    Result:  OK

    OK 

    See step  12

  12. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - MOTOR RESOLVER) 
    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 service info because this may cause a malfunction.

    2. Disconnect the connector from the inverter with converter assembly.
    3. Disconnect the motor resolver connector.
      GTY522833Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      F51-1 (MRF) - A38-40 (MRF) Power switch off Below 1 Ω
      F51-5 (MRFG) - A38-29 (MRFG) Power switch off Below 1 Ω
      F51-2 (MSN) - A38-39 (MSN) Power switch off Below 1 Ω
      F51-6 (MSNG) - A38-28 (MSNG) Power switch off Below 1 Ω
      F51-3 (MCS) - A38-38 (MCS) Power switch off Below 1 Ω
      F51-7 (MCSG) - A38-27 (MCSG) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      F51-1 (MRF) or A38-40 (MRF) - Body ground and other terminals Power switch off 1 MΩ or higher
      F51-5 (MRFG) or A38-29 (MRFG) - Body ground and other terminals Power switch off 1 MΩ or higher
      F51-2 (MSN) or A38-39 (MSN) - Body ground and other terminals Power switch off 1 MΩ or higher
      F51-6 (MSNG) or A38-28 (MSNG) - Body ground and other terminals Power switch off 1 MΩ or higher
      F51-3 (MCS) or A38-38 (MCS) - Body ground and other terminals Power switch off 1 MΩ or higher
      F51-7 (MCSG) or A38-27 (MCSG) - Body ground and other terminals Power switch off 1 MΩ or higher
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Motor Resolver)
      *b 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 transmission assembly.

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

    Result:  OK

    OK 

    REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY 

    (See service information). Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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