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Home >> Lexus >> 2010 >> GS 450h >> Repair and Diagnosis (Single Page) >> Hybrid/Electric Powertrain >> Testing and Diagnosis >> Hybrid Vehicle Control (Diagnostic Codes (P0A10-263-P0A78-287) >> Hybrid Control System >> DTC P0A1A-200: Generator Control Module; DTC P0A1A-792: Generator Control Module; DTC P0A1A-793: Generator Control Module >> Procedure
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DTC P0A1A-200: Generator Control Module; DTC P0A1A-792: Generator Control Module; DTC P0A1A-793: Generator Control Module: Procedure

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

      Result

      DTC No. Relevant Diagnosis
      P0A4B-253, P0A4C-513, P0A4D-255 Generator resolver circuit

    YES → GO TO DTC CHART DIAGNOSTIC TROUBLE CODE CHART 

    NO: Go to next step 

  2. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR) 
    1. Turn the power switch off.
    2. Check the connection of the low voltage connector of the inverter with converter assembly.
      Fig 1: Identifying Connection Of The Low Voltage Connector Of The Inverter With Converter Assembly
      GTY146631Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result

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

    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. Remove the service plug grip.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair service information because this may cause a malfunction.

    2. Disconnect connector A60 from the inverter with converter assembly.
      Fig 2: Identifying A60 Inverter With Converter Assembly Connector Terminals
      GTY142140Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Turn the power switch on (IG).
    4. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Specified Condition
      GRF (A60-1) - Body ground Below 1 V
      GRFG (A60-12) - Body ground Below 1 V
      GSN (A60-14) - Body ground Below 1 V
      GSNG (A60-3) - Body ground Below 1 V
      GCS (A60-13) - Body ground Below 1 V
      GCSG (A60-2) - Body ground Below 1 V
      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.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK GENERATOR RESOLVER 
    1. Turn the power switch off.
      Fig 3: Identifying A60 Inverter With Converter Assembly Connector Terminals
      GTY142140Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Specified Condition
      GRF (A60-1) - GRFG (A60-12) 4.2 to 12.5 Ω
      GSN (A60-14) - GSNG (A60-3) 9.8 to 20.1 Ω
      GCS (A60-13) - GCSG (A60-2) 9.8 to 20.1 Ω

      Standard resistance (Check for short)

      Tester Connection Specified Condition
      GRF (A60-1) or GRFG (A60-12) - Body ground 10 kΩ or more
      GSN (A60-14) or GSNG (A60-3) - Body ground 10 kΩ or more
      GCS (A60-13) or GCSG (A60-2) - Body ground 10 kΩ or more
      GRF (A60-1) - GSN (A60-14) 10 kΩ or more
      GRF (A60-1) - GSNG (A60-3) 10 kΩ or more
      GRF (A60-1) - GCS (A60-13) 10 kΩ or more
      GRF (A60-1) - GCSG (A60-2) 10 kΩ or more
      GRFG (A60-12) - GSN (A60-14) 10 kΩ or more
      GRFG (A60-12) - GSNG (A60-3) 10 kΩ or more
      GRFG (A60-12) - GCS (A60-13) 10 kΩ or more
      GRFG (A60-12) - GCSG (A60-2) 10 kΩ or more
      GSN (A60-14) - GCS (A60-13) 10 kΩ or more
      GSN (A60-14) - GCSG (A60-2) 10 kΩ or more
      GSNG (A60-3) - GCS (A60-13) 10 kΩ or more
      GSNG (A60-3) - GCSG (A60-2) 10 kΩ or more

    OK → See step   7 

    NG: Go to next step 

  5. CHECK CONNECTOR CONNECTION CONDITION (GENERATOR RESOLVER CONNECTOR) 
    1. Check the connection of the generator resolver connector.
      Fig 4: Identifying Connection Of Generator Resolver Connector
      GTY124381Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result

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

    NG → CONNECT SECURELY 

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - GENERATOR RESOLVER) 
    1. Disconnect connector E87 from the generator resolver.
      Fig 5: Identifying E87 Motor Resolver Connector & A60 Inverter With Converter Assembly Connector Terminals
      GTY146595Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Specified Condition
      GRF (A60-1) - GRF (E87-1) Below 1 Ω
      GRFG (A60-12) - GRFG (E87-5) Below 1 Ω
      GSN (A60-14) - GSN (E87-2) Below 1 Ω
      GSNG (A60-3) - GSNG (E87-6) Below 1 Ω
      GCS (A60-13) - GCS (E87-3) Below 1 Ω
      GCSG (A60-2) - GCSG (E87-7) Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection Specified Condition
      GRF (A60-1) or GRF (E87-1) - Body ground 10 kΩ or more
      GRFG (A60-12) or GRFG (E87-5) - Body ground 10 kΩ or more
      GSN (A60-14) or GSN (E87-2) - Body ground 10 kΩ or more
      GSNG (A60-3) or GSNG (E87-6) - Body ground 10 kΩ or more
      GCS (A60-13) or GCS (E87-3) - Body ground 10 kΩ or more
      GCSG (A60-2) or GCSG (E87-7) - Body ground 10 kΩ or more
      GRF (A60-1) - GSN (A60-14) 10 kΩ or more
      GRF (A60-1) - GSNG (A60-3) 10 kΩ or more
      GRF (A60-1) - GCS (A60-13) 10 kΩ or more
      GRF (A60-1) - GCSG (A60-2) 10 kΩ or more
      GRFG (A60-12) - GSN (A60-14) 10 kΩ or more
      GRFG (A60-12) - GSNG (A60-3) 10 kΩ or more
      GRFG (A60-12) - GCS (A60-13) 10 kΩ or more
      GRFG (A60-12) - GCSG (A60-2) 10 kΩ or more
      GSN (A60-14) - GCS (A60-13) 10 kΩ or more
      GSN (A60-14) - GCSG (A60-2) 10 kΩ or more
      GSNG (A60-3) - GCS (A60-13) 10 kΩ or more
      GSNG (A60-3) - GCSG (A60-2) 10 kΩ or more

      HINT: 

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   11 

  7. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - MOTOR RESOLVER) See step   3 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. CHECK MOTOR RESOLVER See step   4 

    NG → See step   12 

    OK: Go to next step 

  9. CHECK CONNECTOR CONNECTION CONDITION (MOTOR RESOLVER CONNECTOR) See step   5 

    NG → CONNECT SECURELY 

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - MOTOR RESOLVER) See step   6 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   11 

  11. REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY. Refer to COMPONENTS 
  12. REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to COMPONENTS 
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