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Terminals Of Ecu

WARNING: This page is about a different car, the 2008 Toyota FJ Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK MAIN BODY ECU 
    1. Disconnect the 1B, 1E, 1F, 1L and E6 main body ECU connectors.
      Fig 1: Identifying 1B, 1E, 1F, 1L & E6 Main Body ECU Connectors Terminals (1 Of 2)
      G05115218Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 2: Identifying 1B, 1E, 1F, 1L & E6 Main Body ECU Connectors Terminals (2 Of 2)
      G05115219Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage of the wire harness side connectors.

      Standard voltage: 

      MAIN BODY ECU

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      BECU (1B-4) - Body ground W-R - Body ground Power source (+B) Always 11 to 14 V
      BECU (1L-4) - Body ground W-R - Body ground Power source (+B) Always 11 to 14 V
      BECU (1F-12) - Body ground W-R - Body ground Power source (+B) Always 11 to 14 V
      BDR1 (1E-9) - Body ground B-Y - Body ground Power source (+B) Always 11 to 14 V
      MPX2 (E6-23) - Body ground BR-R - Body ground Multiplex communication signal During communication Signal waveform

      If the result is not as specified, there may be a malfunction on the wire harness side.

  2. CHECK BACK DOOR ECU 
    1. Disconnect the S2 ECU connector.
      Fig 3: Identifying Back Door ECU Connector Terminals
      G05115220Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage of the wire harness side connector.

      Standard voltage: 

      BACK DOOR ECU

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      GND (S2-3) - Body ground W-B - Body ground Ground for main power supply Ground for main power supply Below 1 V
      BECU (S2-5) - GND (S2-3) W-R - W-B Power source (+B) Always 11 to 14 V
      BDR (S2-4) - GND (S2-3) L-0 - W-B Power source (+B) Always 11 to 14V
      MPX2 (S2-1) - Body ground BR-R - Body ground Multiplex communication signal During communication Signal waveform
      SIG (S2-6) - Body ground B-R - Body ground Power source (IG) Ignition switch ON 11 to 14 V

      If the result is not as specified, there may be a malfunction on the wire harness side.