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Diagnosis System

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. DESCRIPTION 
    1. Push button start system data and its Diagnostic Trouble Code (DTCs) can be read in the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use Techstream to check for malfunctions and perform repairs.
  2. CHECK DLC3 
    1. The ECU uses ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.
      Fig 1: Identifying DLC3 Connector Terminal Identification
      GTY103674Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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) CAN bus line Ignition switch off* 54 to 69 Ω
      CANH (6) - CG (4) HIGH-level CAN bus line Ignition switch off* 200 Ω or higher
      CANL (14) - CG (4) LOW-level CAN bus line Ignition switch off* 200 Ω or higher
      CANH (6) - BAT (16) HIGH-level CAN bus line Ignition switch off* 6 kΩ or higher
      CANL (14) - BAT (16) LOW-level CAN bus line Ignition switch off* 6 kΩ or higher
      NOTE:

      *Before measuring the resistance, leave the vehicle as it is for at least 1 minute and do not operate the ignition switch, or any other switches or the doors.

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

      HINT: 

      Connect the cable of Techstream to DLC3, turn the ignition switch to the ON position 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 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 
    1. Inspect the battery voltage.

      Voltage

      11 to 14 V

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

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