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Diagnosis System

  1. CHECK DLC3 

    The vehicle's ECU uses the ISO 15765-4 communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.

    Fig 1: Identifying DLC3 Terminals
    G04474949Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    DLC3 TERMINALS RESISTANCE SPECIFICATION

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

    HINT:

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

    • If communication is normal when the Techstream is connected to another vehicle, inspect the DLC3 on the original vehicle.
    • If communication is still not possible when the Techstream is connected to another vehicle, the problem may be in the Techstream itself. Consult the Service Department listed in the Techstream's instruction
  2. WARNING LIGHT 
    1. When a problem occurs in the electric power steering system, the PS warning is indicated on the multi-display and the master warning light on the combination meter comes on to inform the driver of the problem.