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Diagnosis System

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. DESCRIPTION 
    1. The main body ECU controls the functions of the multiplex communication system on the vehicle. Data of the multiplex communication system and the Diagnostic Trouble Codes (DTC) can be read through the Data Link Connector 3 (DLC3) of the vehicle.
  2. CHECK DLC3 
    1. The ECU uses ISO 15765-4 for communication. The terminal arrangement of the DLC3 complies with ISO 15031-3 and matches the ISO 15765-4 format.
      Fig 1: Identifying DLC3 Connector Terminals
      G04828034Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      DLC3 CONNECTOR TERMINALS

      Symbols (Terminal No.) Terminal Description Condition Specified Condition
      SIL (7) - SG (5) Bus "+" line During transmission Pulse generation
      CG (4) - Body ground Chassis ground Always Below 1 Ω
      SG (5) - Body ground Signal ground Always Below 1 Ω
      BAT (16) - Body ground Battery positive Always 11 to 14 V
      CANH (6) - CANL (14) HIGH-level CAN bus line Ignition switch OFF(1) 54 to 69 Ω
      CANH (6) - CG (4) HIGH-level CAN bus line Ignition switch OFF(1) 200 Ω or more
      CANL (14) - CG (4) LOW-level CAN bus line Ignition switch OFF(1) 200 Ω or more
      CANH (6) - BAT (16) HIGH-level CAN bus line Ignition switch OFF(1) 6 kΩ or more
      CANL (14) - BAT (16) LOW-level CAN bus line Ignition switch OFF(1) 6 kΩ or more
      (1) Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors.

      If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector.

    2. Techstream

      HINT:

      Connect the cable of the Techstream to the CAN VIM, connect the CAN VIM to the DLC3, turn the ignition switch ON* and attempt to use the tester. If the display indicates that a communication error has occurred, there is a problem either with the vehicle or with the tester.

      • If communication is normal when the tester is connected to another vehicle, inspect the DLC3 of the original vehicle.
      • If communication is still not possible when the tester is connected to another vehicle, the problem may be in the tester itself. Consult the Service Department listed in the tester's instruction manual.
  3. INSPECT BATTERY VOLTAGE 

    Standard voltage: 

    11 to 14 V 

    If the voltage is below 11V, recharge or replace the battery before proceeding.

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