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Terminals Of Ecu [12/2019 - 11/2023]

  1. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 
    GTY851097Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

      Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023]

    2. Reconnect the instrument panel junction block assembly connectors.
    3. Measure the voltage and resistance according to the value(s) in the table below.
      Terminal No. (Symbol) Terminal Description Condition Specified Condition
      MB-11 (GND1) - Body ground Ground Always Below 1 Ω
      H42-19 (GND2) - Body ground Ground Always Below 1 Ω
      MB-30 (ACC) - Body ground ACC power supply Ignition switch ACC 11 to 14 V
      Ignition switch off Below 1 V
      MB-31 (BECU) - Body ground Auxiliary battery power supply Ignition switch off*1
      Always*2
      11 to 14 V
      MB-32 (IG) - Body ground IG power supply Ignition switch ON 11 to 14 V
      Ignition switch off Below 1 V
      1. *1: for HV Model
      2. *2: for Gasoline Model
    4. Install the main body ECU (multiplex network body ECU) to the instrument panel junction block assembly.

      Refer to INSTALLATION [12/2019 - 10/2022] , or refer to INSTALLATION [10/2022 - 11/2023]

    5. Measure the voltage and check for pulses according to the value(s) in the table below.
      Terminal No. (Symbol) Terminal Description Condition Specified Condition
      4C-29 (BZR) - Body ground Wireless door lock buzzer output Active Test Wireless Buzzer is OFF Below 1 V
      Active Test Wireless Buzzer is ON Pulse generation
      (frequency: 2 kHz, high voltage: 11 to 14 V, low voltage: below 1 V)
  2. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    GTY862615Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *A for Gasoline Model - -
    1. Disconnect the H48 certification ECU (smart key ECU assembly) connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.
      Terminal No. (Symbol) Terminal Description Condition Specified Condition
      H48-4 (+B) - Body ground Auxiliary battery power supply Ignition switch off*1
      Always*2
      11 to 14 V
      H48-18 (E) - Body ground Ground Always Below 1 Ω
      1. *1: for HV Model
      2. *2: for Gasoline Model
    3. Reconnect the H48 certification ECU (smart key ECU assembly) connector.
    4. Check for pulses according to the value(s) in the table below.
      Terminal No. (Symbol) Terminal Description Condition Specified Condition
      M5-18 (RCO) - H48-18 (E) Output to electrical key and tire pressure warning ECU and receiver
      (Power supply for electrical key and tire pressure warning ECU and receiver. Certification ECU (smart key ECU assembly) outputs 5 V when receiver starts operating.)
      Procedure: 
      1. Turn ignition switch off
      2. Bring electrical key transmitter sub-assembly outside detection area but within wireless function operational area
      3. Press lock or unlock switch of electrical key transmitter sub-assembly
      Plus generation (See waveform 1)
      M5-19 (RDAM) - H48-18 (E) Electrical key and tire pressure warning ECU and receiver communication circuit Procedure: 
      1. Turn ignition switch off
      2. Lock all doors
      3. Bring electrical key transmitter sub-assembly outside detection area but within wireless function operational area
      4. Press lock or unlock switch of electrical key transmitter sub-assembly
      Plus generation (See waveform 2)
      M5-20 (CSEL) - H48-18 (E) Communication channel switching circuit Procedure: 
      1. Turn ignition switch off
      2. Close all doors
      No pulse generation → Pulse generation
    5. Using an oscilloscope, check waveform 1.

      HINT: 

      The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

      GTY751928Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Before lock or unlock switch of electrical key transmitter sub-assembly pressed
      *b After lock or unlock switch of electrical key transmitter sub-assembly pressed
      WAVEFORM 1 (REFERENCE)

      Item Content
      Tester connection M5-18 (RCO) - H48-18 (E)
      Tool setting 2 V/DIV., 500 ms/DIV.
      Condition Procedure:
      1. Turn ignition switch off
      2. Bring electrical key transmitter sub-assembly outside detection area but within wireless function operational area
      3. Press lock or unlock switch of electrical key transmitter sub-assembly
    6. Using an oscilloscope, check waveform 2.

      HINT: 

      The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

      GTY746864Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Before lock or unlock switch of electrical key transmitter sub-assembly pressed
      *b After lock or unlock switch of electrical key transmitter sub-assembly pressed
      WAVEFORM 2 (REFERENCE)

      Item Content
      Tester connection M5-19 (RDAM) - H48-18 (E)
      Tool setting 5 V/DIV., 500 ms/DIV.
      Condition Procedure:
      1. Turn ignition switch off
      2. Lock all doors
      3. Bring electrical key transmitter sub-assembly outside detection area but within wireless function operational area
      4. Press lock or unlock switch of electrical key transmitter sub-assembly