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DTC P0A1A-200: Generator Control Module; DTC P0A1A-792: Generator Control Module; DTC P0A1A-793: Generator Control Module [10/2014 - 09/2016]: 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 for DTCs.

      Powertrain > Hybrid Control > Trouble Codes 

      Result

      Result Proceed to
      P0A1A-200, 792 or 793 only is output, or DTCs except the ones in the table below are also output. A
      Any of the following DTCs are also output. B
      Relevant DTC
      P0A3F-243 Drive Motor "A" Position Sensor Circuit
      P0A45-669 Drive Motor "B" 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: 

    GO TO DTC CHART (HYBRID CONTROL SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2014 - 09/2016] 

    Result: 

    See step  2

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

    Refer to PROCEDURE - Step 3

    Result

    Result Proceed to
    OK A
    NG (The connector is not connected securely.) B
    NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    Result: 

    CONNECT SECURELY 

    Result: 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    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 procedures because this may cause a malfunction.

    2. Disconnect the C49 inverter with converter assembly connector.
    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.

      Standard Voltage

      Tester Connection Condition Specified Condition
      C49-1 (GRF) - Body ground Power switch on (IG) Below 1 V
      C49-7 (GRFG) - Body ground Power switch on (IG) Below 1 V
      C49-2 (GSN) - Body ground Power switch on (IG) Below 1 V
      C49-8 (GSNG) - Body ground Power switch on (IG) Below 1 V
      C49-3 (GCS) - Body ground Power switch on (IG) Below 1 V
      C49-9 (GCSG) - Body ground Power switch on (IG) Below 1 V
      GTY520103Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)
      NOTE:

      Turning the power switch on (IG) with 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. Reconnect the C49 inverter with converter assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    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 procedures because this may cause a malfunction.

    2. Disconnect the C49 inverter with converter assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      C49-1 (GRF) - C49-7 (GRFG) Power switch off 4.2 to 12.5 Ω
      C49-2 (GSN) - C49-8 (GSNG) Power switch off 9.8 to 20.1 Ω
      C49-3 (GCS) - C49-9 (GCSG) Power switch off 9.8 to 20.1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      C49-1 (GRF) or C49-7 (GRFG) - Body ground and other terminals Power switch off 1 MΩ or higher
      C49-2 (GSN) or C49-8 (GSNG) - Body ground and other terminals Power switch off 1 MΩ or higher
      C49-3 (GCS) or C49-9 (GCSG) - Body ground and other terminals Power switch off 1 MΩ or higher
      GTY509337Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)
    4. Reconnect the C49 inverter with converter assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    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 procedures because this may cause a malfunction.

    2. Disconnect the C49 inverter with converter assembly connector.
    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.

      Standard Voltage

      Tester Connection Condition Specified Condition
      C49-4 (MRF) - Body ground Power switch on (IG) Below 1 V
      C49-11 (MRFG) - Body ground Power switch on (IG) Below 1 V
      C49-5 (MSN) - Body ground Power switch on (IG) Below 1 V
      C49-12 (MSNG) - Body ground Power switch on (IG) Below 1 V
      C49-6 (MCS) - Body ground Power switch on (IG) Below 1 V
      C49-13 (MCSG) - Body ground Power switch on (IG) Below 1 V
      GTY509335Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)
      NOTE:

      Turning the power switch on (IG) with 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. Reconnect the C49 inverter with converter assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    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 procedures because this may cause a malfunction.

    2. Disconnect the C49 inverter with converter assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      C49-4 (MRF) - C49-11 (MRFG) Power switch off 4.2 to 12.5 Ω
      C49-5 (MSN) - C49-12 (MSNG) Power switch off 9.8 to 20.1 Ω
      C49-6 (MCS) - C49-13 (MCSG) Power switch off 9.8 to 20.1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      C49-4 (MRF) or C49-11 (MRFG) - Body ground and other terminals Power switch off 1 MΩ or higher
      C49-5 (MSN) or C49-12 (MSNG) - Body ground and other terminals Power switch off 1 MΩ or higher
      C49-6 (MCS) or C49-13 (MCSG) - Body ground and other terminals Power switch off 1 MΩ or higher
      GTY509336Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)
    4. Reconnect the C49 inverter with converter assembly connector.

      Result

      Proceed to
      OK (for AWD)
      OK (for 2WD)
      NG

    Result: 

    OK (for 2WD) 

    See step  9

    Result: 

    NG 

    See step  16

    Result: 

    OK (for AWD) 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - REAR 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 procedures because this may cause a malfunction.

    2. Disconnect the A58 inverter with converter assembly connector.
    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.
      GTY502521Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)

      Standard Voltage

      Tester Connection Condition Specified Condition
      A58-34 (RRF) - Body ground Power switch on (IG) Below 1 V
      A58-23 (RRFG) - Body ground Power switch on (IG) Below 1 V
      A58-33 (RSN) - Body ground Power switch on (IG) Below 1 V
      A58-22 (RSNG) - Body ground Power switch on (IG) Below 1 V
      A58-32 (RCS) - Body ground Power switch on (IG) Below 1 V
      A58-21 (RCSG) - Body ground Power switch on (IG) 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.

    6. Turn the power switch off.
    7. Disconnect the cable from the negative (-) auxiliary battery terminal.
    8. Reconnect the A58 inverter with converter assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK REAR 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 procedures because this may cause a malfunction.

    2. Disconnect the A58 inverter with converter assembly connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY502520Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A58-34 (RRF) - A58-23 (RRFG) Power switch off 4.2 to 12.5 Ω
      A58-33 (RSN) - A58-22 (RSNG) Power switch off 9.8 to 20.1 Ω
      A58-32 (RCS) - A58-21 (RCSG) Power switch off 9.8 to 20.1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A58-34 (RRF) or A58-23 (RRFG) - Body ground and other terminals Power switch off 1 MΩ or higher
      A58-33 (RSN) or A58-22 (RSNG) - Body ground and other terminals Power switch off 1 MΩ or higher
      A58-32 (RCS) or A58-21 (RCSG) - Body ground and other terminals Power switch off 1 MΩ or higher
    4. Connect the A58 inverter with converter assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  14

    Result: 

    OK 

    See step  9

  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.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [10/2014 - ]

      GTY516238Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK

      - The connector is connected securely.

      - The terminals are not deformed and are connected securely.

      - No water or foreign matter in the connector.

      Result

      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    Result: 

    CONNECT SECURELY 

    Result: 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    See step  10

  10. 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.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [10/2014 - ]

      GTY521621Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK

      - The connector is connected securely.

      - The terminals are not deformed and are connected securely.

      - No water or foreign matter in the connector.

      Result

      Result Proceed to
      OK (for AWD) A
      OK (for 2WD) B
      NG (The connector is not connected securely.) C
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) D

    Result: 

    REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to  REMOVAL [10/2014 - 09/2016] 

    Result: 

    CONNECT SECURELY 

    Result: 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    See step  11

  11. CHECK CONNECTOR CONNECTION CONDITION (REAR MOTOR RESOLVER CONNECTOR) 
    1. Check the connection condition of the rear 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.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [10/2014 - ]

      GTY516236Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK

      - The connector is connected securely.

      - The terminals are not deformed and are connected securely.

      - No water or foreign matter in the connector.

      Result

      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    Result: 

    REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to  REMOVAL [10/2014 - 09/2016] 

    Result: 

    CONNECT SECURELY 

    Result: 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  12. 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.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [10/2014 - ]

      GTY516238Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK

      - The connector is connected securely.

      - The terminals are not deformed and are connected securely.

      - No water or foreign matter in the connector.

      Result

      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    Result: 

    CONNECT SECURELY 

    Result: 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    See step  13

  13. INSPECT HYBRID VEHICLE TRANSAXLE ASSEMBLY (GENERATOR RESOLVER) 
    1. Disconnect the C41 generator resolver connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY771126Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Generator Resolver (Hybrid Vehicle Transaxle Assembly))

      Standard Resistance

      Tester Connection Condition Specified Condition
      1 (GRF) - 5 (GRFG) Power switch off 5.8 to 11.8 Ω
      2 (GSN) - 6 (GSNG) Power switch off 11.7 to 17.7 Ω
      3 (GCS) - 7 (GCSG) Power switch off 11.7 to 17.7 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      1 (GRF) - Body ground and other terminals (except 5 (GRFG)) Power switch off 1 MΩ or higher
      5 (GRFG) - Body ground and other terminals (except 1 (GRF)) Power switch off 1 MΩ or higher
      2 (GSN) - Body ground and other terminals (except 6 (GSNG)) Power switch off 1 MΩ or higher
      6 (GSNG) - Body ground and other terminals (except 2 (GSN)) Power switch off 1 MΩ or higher
      3 (GCS) - Body ground and other terminals (except 7 (GCSG)) Power switch off 1 MΩ or higher
      7 (GCSG) - Body ground and other terminals (except 3 (GCS)) Power switch off 1 MΩ or higher

      HINT: 

      The generator resolver is not available as a supply part. If it requires replacement, replace the hybrid vehicle transaxle assembly.

    3. Reconnect the C41 generator resolver connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    NG 

    REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY. Refer to  REMOVAL [10/2014 - 09/2015]  , or refer to  REMOVAL [09/2015 - ] 

  14. CHECK CONNECTOR CONNECTION CONDITION (REAR MOTOR RESOLVER CONNECTOR) 
    1. Check the connection condition of the rear 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.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [10/2014 - ]

      GTY516236Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK

      - The connector is connected securely.

      - The terminals are not deformed and are connected securely.

      - No water or foreign matter in the connector.

      Result

      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    Result: 

    CONNECT SECURELY 

    Result: 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    See step  15

  15. INSPECT REAR TRACTION MOTOR WITH TRANSAXLE ASSEMBLY (REAR MOTOR RESOLVER) 
    1. Disconnect the R3 rear motor resolver connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      1 (RRF) - 4 (RRFG) Power switch off 5.8 to 11.8 Ω
      2 (RSN) - 5 (RSNG) Power switch off 11.7 to 17.7 Ω
      3 (RCS) - 6 (RCSG) Power switch off 11.7 to 17.7 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      1 (RRF) - Body ground and other terminals (except 4 (RRFG)) Power switch off 1 MΩ or higher
      4 (RRFG) - Body ground and other terminals (except 1 (RRF)) Power switch off 1 MΩ or higher
      2 (RSN) - Body ground and other terminals (except 5 (RSNG)) Power switch off 1 MΩ or higher
      5 (RSNG) - Body ground and other terminals (except 2 (RSN)) Power switch off 1 MΩ or higher
      3 (RCS) - Body ground and other terminals (except 6 (RCSG)) Power switch off 1 MΩ or higher
      6 (RCSG) - Body ground and other terminals (except 3 (RCS)) Power switch off 1 MΩ or higher

      HINT: 

      The rear motor resolver is not available as a supply part. If it requires replacement, replace the rear traction motor with transaxle assembly.

      GTY716728Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Rear Motor Resolver (Rear Traction Motor with Transaxle Assembly))
    3. Reconnect the R3 rear motor resolver connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    NG 

    REPLACE REAR TRACTION MOTOR WITH TRANSAXLE ASSEMBLY. Refer to  REMOVAL [10/2014 - ] 

  16. 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.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [10/2014 - ]

      GTY521621Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK

      - The connector is connected securely.

      - The terminals are not deformed and are connected securely.

      - No water or foreign matter in the connector.

      Result

      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    Result: 

    CONNECT SECURELY 

    Result: 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    See step  17

  17. INSPECT HYBRID VEHICLE TRANSAXLE ASSEMBLY (MOTOR RESOLVER) 
    1. Disconnect the C44 motor resolver connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY716727Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Motor Resolver (Hybrid Vehicle Transaxle Assembly))

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      1 (MRF) - 4 (MRFG) Power switch off 5.8 to 11.8 Ω
      2 (MSN) - 5 (MSNG) Power switch off 11.7 to 17.7 Ω
      3 (MCS) - 6 (MCSG) Power switch off 11.7 to 17.7 Ω

      Standard Resistance (Check for Short)

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

      HINT: 

      The motor resolver is not available as a supply part. If it requires replacement, replace the hybrid vehicle transaxle assembly.

    3. Reconnect the C44 motor resolver connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    NG 

    REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY. Refer to  REMOVAL [10/2014 - 09/2015]  , or refer to  REMOVAL [09/2015 - ]