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Diagnosis System [08/2012 - ]

WARNING: This page is about a different variant/trim than selected.
  1. DIAGNOSIS SYSTEM 
    1. Inspect the battery voltage.
      Fig 1: Identifying DLC3 Connector Terminals
      GTY134295Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage

      11 to 14 V

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

    2. Check the DLC3.

      The 4WD control ECU uses CAN and the ISO 9141-2 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.

      Verify the conditions listed in the table below.

      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 Engine switch off 54 to 67 Ω
      CANH (6) - Battery positive HIGH-level CAN bus line Engine switch off 1 MΩ or higher
      CANH (6) - CG (4) HIGH-level CAN bus line Engine switch off 3 kΩ or higher
      CANL (14) - Battery positive LOW-level CAN bus line Engine switch off 1 MΩ or higher
      CANL (14) - CG (4) LOW-level CAN bus line Engine switch off 3 kΩ or higher

      HINT: 

      If the display shows a communication error message when the cable of the Techstream is connected to the DLC3, the engine switch is turned on (IG) and the Techstream is operated, there is a problem on either the vehicle side or the tester side.

      • If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
      • If communication is still not possible when the tester is connected to another vehicle, the problem is probably in the tester itself. Consult the Service Department listed in the tester's operator's manual.
  2. FUNCTION OF 4WD INDICATOR 
    1. The 4WD indicator light in the combination meter assembly (multi-information display) warns the driver of abnormal or poor condition of the four wheel drive control system.
      Fig 2: Identifying Function Of 4WD Indicator Display
      GTY353229Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. CHECK 4WD INDICATOR LIGHT 
    1. Using SST, connect terminals TC and CG of the DLC3 (to enter the DTC output mode).
      Fig 3: Identifying DLC3 Connector Terminals
      GTY124019Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • SST: 09843-18040 
    2. Turn the engine switch on (IG).
    3. "DIAG" is displayed on the multi-information display, and the 4WD control ECU checks the system for malfunctions.
      • If the 4WD control system is normal, "DIAG AWD OK" will be displayed on the multi-information display.
        Fig 4: Identifying DIAG AWD OK Display
        GTY350675Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • If the 4WD control system is not normal, "DIAG AWD XX (DTC)" will be displayed on the multi-information display.
        Fig 5: Identifying DIAG AWD XX (DTC Display)
        GTY354104Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • Although the Test Mode is not set for the 4WD control system, the message shown in the illustration will be displayed on the multi-information display when the Test Mode is activated to check the VSC, etc.
        Fig 6: Identifying AWD TEST MODE Display
        GTY350764Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT: 

      • Test Mode DTCs will not be stored because the Test Mode is not set.
      • On the multi-information display, VSC, TIRE PRESSURE and 4WD are displayed in order.
      • If the systems above are not displayed on the multi-information display, there may be a malfunction in "TC and CG Terminal Circuit". Refer to TC and CG Terminal Circuit .
      • If the 4WD indicator light check result is not normal, proceed to troubleshooting for the 4WD indicator light circuit.
        Trouble Area See procedure
        4WD indicator light (Remains on) Refer to PROBLEM SYMPTOMS TABLE [08/2012 - ] 
        4WD indicator light (Does not come on)
  4. FAIL-SAFE FUNCTION 
    1. If following malfunctions occur, the 4WD control ECU will stop the function of 4WD control system or partly change the function to control the system.
      Malfunction Control
      Malfunction in a speed sensor Stop the function
      Malfunction in the steering angle sensor and throttle signal line Partly change the function