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Diagnosis System

  1. DESCRIPTION 

    The ECU controls the cruise control system of the vehicle. The data and DTCs relating to the cruise control system can be read from the DLC3 of the vehicle. If either DTC is not displayed when checking for DTCs, there may be a problem with the combination meter or the CAN communication and multiplex communication system. Use the intelligent tester to check and solve the problem.

  2. CHECK DLC3 
    1. The vehicle's hybrid vehicle control ECU uses the 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 Terminals (CANL And BAT)
      G04828034Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TERMINALS NO. AND SPECIFIED CONDITION

      Terminal No. (Symbols) 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 10 to 14 V
      CANH (6) - CANL (14) 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 higher
      CANL (14) - CG (4) LOW-level CAN bus line Ignition switch off(1) 200 Ω or higher
      CANH (6) - BAT (16) HIGH-level CAN bus line Ignition switch off(1) 6 kΩ or higher
      CANL (14) - BAT (16) LOW-level CAN bus line Ignition switch off(1) 6 kΩ or higher
      NOTE:
      (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. Connect the cable of the intelligent tester to the 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 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. CHECK INDICATOR 
    1. Turn the ignition switch on.
      Fig 2: Identifying Cruise Main Indicator Light
      G05279857Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check that the CRUISE main indicator light illuminates when the cruise control main switch is turned ON, and that the indicator light turns off when the main switch is turned OFF. If the results are not as specified, inspect the CRUISE main indicator light circuit (See CRUISE MAIN INDICATOR LIGHT CIRCUIT ).

      HINT:

      • While driving with cruise control, the hybrid vehicle control ECU activates AUTO CANCEL of the cruise control system when a malfunction in one of the following occurs: vehicle speed sensors, stop light switch or other related parts. When AUTO CANCEL is activated, the CRUISE main indicator light outputs the blinking pattern shown to the left. At the same time, data of the malfunction is stored as a DTC.
    Fig 3: Cruise Main Indicator Light Blinking Pattern
    G05279858Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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