DTC B2799-86: Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid [11/2018 - ]: Procedure

2020 Toyota RAV4 XLE, AWDSECTION Procedure
WARNING: This page is about a different variant/trim than selected.
  1. REGISTER ECU COMMUNICATION ID (ID CODE BOX (IMMOBILISER CODE ECU) - HYBRID VEHICLE CONTROL ECU ASSEMBLY) 
    1. Register the communication ID codes.

      HINT: 

      Refer to the Registration.

      Refer to REGISTRATION [11/2018 - 10/2019] , or refer to REGISTRATION [10/2019 - 12/2021] , or refer to REGISTRATION [12/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (TERMINAL IMO) 
    1. Using an oscilloscope, check the waveform.
      GTY857455Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Hybrid Vehicle Control ECU Assembly)
      *b Waveform
      *c Approximately 160 ms. *d Approximately 270 ms.

      Measurement Condition

      Tester Connection Condition Tool Setting Specified Condition
      A30-23 (IMO) - Body ground Within 3 seconds of hybrid control system start or within 3 seconds of power switch turned on (IG) after cable disconnected and reconnected to auxiliary battery 2 V/DIV., 500 ms./DIV. Pulse generation
      (See waveform)

      Result

      Result Proceed to
      Normal waveform A
      Terminal IMO stuck low (2.4 V or less) B
      Waveform length or shape is abnormal, or IMO terminal stuck at Hi (12 V) C

    Result: 

    See step  6

    Result: 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY. Refer to  REMOVAL [11/2018 - 02/2019]  , or refer to  REMOVAL [02/2019 - 10/2019]  , or refer to  REMOVAL [10/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021]  , or refer to  REMOVAL [12/2021 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023]  , or refer to  REMOVAL [10/2023 - ] 

    Result: 

    See step  3

  3. CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (TERMINAL IMI) 
    1. Using an oscilloscope, check the waveform.
      GTY862146Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Hybrid Vehicle Control ECU Assembly)
      *b Waveform
      *c Approximately 160 ms. *d Approximately 270 ms.

      Measurement Condition

      Tester Connection Condition Tool Setting Specified Condition
      A30-10 (IMI) - Body ground Within 3 seconds of hybrid control system start or within 3 seconds of power switch turned on (IG) after cable disconnected and reconnected to auxiliary battery 2 V/DIV., 500 ms./DIV. Pulse generation
      (See waveform)

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [11/2018 - 02/2019]  , or refer to  REMOVAL [02/2019 - 10/2019]  , or refer to  REMOVAL [10/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021]  , or refer to  REMOVAL [12/2021 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023]  , or refer to  REMOVAL [10/2023 - ] 

    Result: 

    OK 

    See step  4

  4. REGISTER ECU COMMUNICATION ID (ID CODE BOX (IMMOBILISER CODE ECU) - HYBRID VEHICLE CONTROL ECU ASSEMBLY) 
    1. Register the ECU communication ID codes.

      HINT: 

      Refer to the Registration.

      Refer to REGISTRATION [11/2018 - 10/2019] , or refer to REGISTRATION [10/2019 - 12/2021] , or refer to REGISTRATION [12/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  5. CHECK WHETHER HYBRID CONTROL SYSTEM STARTS 
    1. Check that the hybrid control system starts.

      Result

      Result Proceed to
      Hybrid control system was started A
      Hybrid control system was not started B

    Result: 

    END (ECU COMMUNICATION ID HAS NOT BEEN REGISTERED) 

    Result: 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY. Refer to  REMOVAL [11/2018 - 02/2019]  , or refer to  REMOVAL [02/2019 - 10/2019]  , or refer to  REMOVAL [10/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021]  , or refer to  REMOVAL [12/2021 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023]  , or refer to  REMOVAL [10/2023 - ] 

  6. CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (TERMINAL IMO) 
    1. Disconnect the A30 hybrid vehicle control ECU assembly connector.
      GTY844605Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A30-23 (IMO) - Body ground Power switch turned on (IG) using registered electrical key transmitter sub-assembly Terminal IMO stuck low (2.4 V or less)
      Terminal IMO stuck high (12 V)

      Result

      Result Proceed to
      Terminal IMO stuck low (2.4 V or less) A
      Terminal IMO stuck high (12 V) B

    Result: 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY. Refer to  REMOVAL [11/2018 - 02/2019]  , or refer to  REMOVAL [02/2019 - 10/2019]  , or refer to  REMOVAL [10/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021]  , or refer to  REMOVAL [12/2021 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023]  , or refer to  REMOVAL [10/2023 - ] 

    Result: 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - HYBRID VEHICLE CONTROL ECU ASSEMBLY) 
    1. Disconnect the G57 ID code box (immobiliser code ECU) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G57-3 (EFII) - A30-23 (IMO) Always Below 1 Ω
      G57-3 (EFII) or A30-23 (IMO) - Other terminals and body ground Always 10 kΩ or higher
      G57-4 (EFIO) - A30-10 (IMI) Always Below 1 Ω
      G57-4 (EFIO) or A30-10 (IMI) - Other terminals and body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [11/2018 - 02/2019]  , or refer to  REMOVAL [02/2019 - 10/2019]  , or refer to  REMOVAL [10/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021]  , or refer to  REMOVAL [12/2021 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023]  , or refer to  REMOVAL [10/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

RENDER: 1.0x

NO RELATED

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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  • Brakes feel soft, pull hard to one side, or make grinding noises.
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