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DTC B2782: Power Source Control ECU Malfunction [09/2014 - 01/2023]: Procedure

  1. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) (MOTOR ACTIVATION COMMAND SIGNAL) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    2. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY505493Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Steering Lock ECU (Steering Lock Actuator Assembly))

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-1 (GND) - Body ground Always Below 1 Ω
    4. Reconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    5. Move the shift lever to P and turn the engine switch off.
    6. Check the signal waveform according to the condition(s) in the table below.
      GTY504133Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))
      *b Steering Lock Motor not Operating
      *c Steering Lock Motor Operating

      Standard Frequency

      Item Content
      Tester Connection O27-3 (IGE) - O27-1 (GND)
      Tool Setting 2 V/DIV., 200 ms./DIV.
      Vehicle Condition Steering lock motor not operating → Operating → Not operating

      HINT: 

      • When taking measurements when the lock motor is stopped, it is not necessary to perform any operations.
      • In order to take measurements when the lock motor is operating, perform either of the following operations:
        • To unlock the steering, carry the key and turn the engine switch on (ACC) or on (IG).
        • To lock the steering, turn the engine switch off with the shift lever in P, and then open a door.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  4

    Result: 

    OK 

    See step  2

  2. CLEAR DTC AND DATA LIST MALFUNCTION RECORD 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2014 - 01/2023]

      Body Electrical > Smart Access > Clear DTCs 

    2. Disconnect the cable from the negative (-) battery terminal, wait for 30 seconds or more, and then reconnect the cable to the negative (-) battery terminal to clear the record of malfunctions stored in the Data List.
      WARNING:

      After turning the engine switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notices before proceeding with work.

      Refer to PRECAUTION [09/2014 - 11/2017] , or refer to PRECAUTION [11/2017 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3

  3. READ VALUE USING TECHSTREAM (POWER SUPPLY SHORT) 
    1. Perform the DTC output confirmation operation.
    2. Check if DTC B2782 is output.

      Refer to DTC CHECK / CLEAR [09/2014 - 01/2023]

      Body Electrical > Smart Access > Trouble Codes 

    3. Use the Data List to check if the steering lock control is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Power Supply Short Record of malfunction of signal sent to steering lock motor (steering lock actuator assembly) from certification ECU (smart key ECU assembly) (short circuit)
      (DTC B2782 is output)      		 OK or NG(Past) OK: No record of malfunction (short circuit)
      NG(Past): Record of malfunction (short circuit) exists      		 This item records malfunctions in the circuit between the certification ECU (smart key ECU assembly) and steering lock motor (steering lock actuator assembly).

      Body Electrical > Smart Access > Data List 

      Tester Display
      Power Supply Short

      Result

      Result Proceed to
      • DTC B2782 is not output.
      • "OK" is displayed on the Techstream.
      		 A
      • DTC B2782 is output.
      • "NG(Past)" is displayed on the Techstream.
      		 B

    Result: 

    A 

    SYSTEM RETURNED TO NORMAL (DTC STORED DUE TO BAD CONNECTION, BUT SYSTEM RETURNED TO NORMAL BY RECONNECTING CONNECTOR) 

    Result: 

    B 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - 03/2019]  , or refer to  DISASSEMBLY [03/2019 - 01/2023] 

  4. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    2. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    3. Disconnect the O6 certification ECU (smart key ECU assembly) connector.
    4. Check for deformation and corrosion of the connector case and terminals.

      OK

      There is no deformation or corrosion of the connector case or terminals.

    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-3 (IGE) - O6-24 (SLR+) Always Below 1 Ω
      O27-3 (IGE) or O6-24 (SLR+) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2014 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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