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Home >> Toyota >> 2014 >> Prius C Two >> Repair and Diagnosis (Single Page) >> Hybrid/Electric Powertrain >> Testing and Diagnosis >> Hybrid Control System (Diagnostic Codes (P0069-273 - P0A75-336)) >> Hybrid Control System >> DTC P0A1A-200: Generator Control Module; DTC P0A1A-792: Generator Control Module; DTC P0A1A-793: Generator Control Module [12/2013 - ] >> Procedure
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DTC P0A1A-200: Generator Control Module; DTC P0A1A-792: Generator Control Module; DTC P0A1A-793: Generator Control Module [12/2013 - ]: Procedure

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

      Result

      Result Proceed to
      Only P0A1A-200, 792 or 793 is output or DTCs except the ones in the table below are also 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 ignition switch off.

    B → See step   13 

    A: Go to next step 

  2. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR) See step   3 

    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. Check that the service plug grip is not installed.
      NOTE:

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

    2. Disconnect connector C28 from the inverter with converter assembly.
    3. Connect the cable to the negative (-) auxiliary battery terminal.
    4. Turn the ignition switch to ON (IG).
    5. Measure the voltage according to the value(s) in the table below.
      GTY337705Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      C28-11 (GRF) - Body ground Ignition switch ON (IG) Below 1 V
      C28-12 (GRFG) - Body ground Ignition switch ON (IG) Below 1 V
      C28-7 (GSN) - Body ground Ignition switch ON (IG) Below 1 V
      C28-8 (GSNG) - Body ground Ignition switch ON (IG) Below 1 V
      C28-10 (GCS) - Body ground Ignition switch ON (IG) Below 1 V
      C28-9 (GCSG) - Body ground Ignition switch ON (IG) Below 1 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)
      NOTE:

      Turning the ignition switch to 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 ignition switch off.
    7. Disconnect the cable from the negative (-) auxiliary battery terminal.
    8. Connect the inverter with converter assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  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 ignition switch to ON (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Disconnect connector C28 from the inverter with converter assembly.
    3. Measure the resistance according to the value(s) in the table below.
      GTY337705Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      C28-11 (GRF) - C28-12 (GRFG) Ignition switch off 7.1 to 21.6 Ω
      C28-7 (GSN) - C28-8 (GSNG) Ignition switch off 13.7 to 34.5 Ω
      C28-10 (GCS) - C28-9 (GCSG) Ignition switch off 12.8 to 32.4 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      C28-11 (GRF) or C28-12 (GRFG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-7 (GSN) or C28-8 (GSNG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-10 (GCS) or C28-9 (GCSG) - Body ground and other terminals Ignition 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.

    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. Check that the service plug grip is not installed.
      NOTE:

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

    2. Disconnect connector C28 from the inverter with converter assembly.
    3. Connect the cable to the negative (-) auxiliary battery terminal.
    4. Turn the ignition switch to ON (IG).
    5. Measure the voltage according to the value(s) in the table below.
      GTY337706Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      C28-1 (MRF) - Body ground Ignition switch ON (IG) Below 1 V
      C28-2 (MRFG) - Body ground Ignition switch ON (IG) Below 1 V
      C28-3 (MSN) - Body ground Ignition switch ON (IG) Below 1 V
      C28-4 (MSNG) - Body ground Ignition switch ON (IG) Below 1 V
      C28-6 (MCS) - Body ground Ignition switch ON (IG) Below 1 V
      C28-5 (MCSG) - Body ground Ignition switch ON (IG) Below 1 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)
      NOTE:

      Turning the ignition switch to 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 ignition switch off.
    7. Disconnect the cable from the negative (-) auxiliary battery terminal.
    8. Connect the inverter with converter assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  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 ignition switch to ON (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Disconnect connector C28 from the inverter with converter assembly.
    3. Measure the resistance according to the value(s) in the table below.
      GTY337706Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      C28-1 (MRF) - C28-2 (MRFG) Ignition switch off 7.1 to 21.6 Ω
      C28-3 (MSN) - C28-4 (MSNG) Ignition switch off 13.7 to 34.5 Ω
      C28-6 (MCS) - C28-5 (MCSG) Ignition switch off 12.8 to 32.4 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      C28-1 (MRF) or C28-2 (MRFG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-3 (MSN) or C28-4 (MSNG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-6 (MCS) or C28-5 (MCSG) - Body ground and other terminals Ignition 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.

    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.

      GTY324464Courtesy 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.

      GTY338180Courtesy 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.

      GTY324464Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG → CONNECT SECURELY 

    OK: Go to next step 

  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 ignition switch to ON (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Disconnect connector C28 from the inverter with converter assembly.
    3. Disconnect the generator resolver connector.
      GTY332811Courtesy 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
      C28-11 (GRF) - C24-1 (GRF) Ignition switch off Below 1 Ω
      C28-12 (GRFG) - C24-5 (GRFG) Ignition switch off Below 1 Ω
      C28-7 (GSN) - C24-2 (GSN) Ignition switch off Below 1 Ω
      C28-8 (GSNG) - C24-6 (GSNG) Ignition switch off Below 1 Ω
      C28-10 (GCS) - C24-3 (GCS) Ignition switch off Below 1 Ω
      C28-9 (GCSG) - C24-7 (GCSG) Ignition switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      C28-11 (GRF) or C24-1 (GRF) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-12 (GRFG) or C24-5 (GRFG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-7 (GSN) or C24-2 (GSN) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-8 (GSNG) or C24-6 (GSNG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-10 (GCS) or C24-3 (GCS) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-9 (GCSG) or C24-7 (GCSG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      TEXT IN ILLUSTRATION

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

      HINT: 

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

    5. Connect the generator resolver connector.
    6. 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.

      GTY338180Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG → CONNECT SECURELY 

    OK: Go to next step 

  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 ignition switch to ON (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Disconnect connector C28 from the inverter with converter assembly.
    3. Disconnect the motor resolver connector.
      GTY325815Courtesy 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
      C28-1 (MRF) - C26-3 (MRF) Ignition switch off Below 1 Ω
      C28-2 (MRFG) - C26-6 (MRFG) Ignition switch off Below 1 Ω
      C28-3 (MSN) - C26-1 (MSN) Ignition switch off Below 1 Ω
      C28-4 (MSNG) - C26-4 (MSNG) Ignition switch off Below 1 Ω
      C28-6 (MCS) - C26-2 (MCS) Ignition switch off Below 1 Ω
      C28-5 (MCSG) - C26-5 (MCSG) Ignition switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      C28-1 (MRF) or C26-3 (MRF) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-2 (MRFG) or C26-6 (MRFG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-3 (MSN) or C26-1 (MSN) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-4 (MSNG) or C26-4 (MSNG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-6 (MCS) or C26-2 (MCS) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      C28-5 (MCSG) or C26-5 (MCSG) - Body ground and other terminals Ignition switch off 1 MΩ or higher
      TEXT IN ILLUSTRATION

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

      HINT: 

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

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   15 

  13. GO TO DTC CHART (HYBRID CONTROL SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [12/2013 - ] 
  14. REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to  COMPONENTS [12/2013 - ] 
  15. REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY. Refer to  COMPONENTS [12/2013 - ] 
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