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Diagnosis System

  1. DESCRIPTION 
    1. The door ECUs control the power window control system functions on the vehicle. Power window control system data and the Diagnostic Trouble Code (DTC) can be read in the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the hand-held tester to check for malfunctions and perform repairs.
  2. CHECK DLC3 

    HINT:

    The vehicle 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 Terminals
    G01442889Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 2: DLC3 Terminals Reference Chart
    G01442890Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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 hand-held tester (with CAN VIM) to the DLC3, turn the ignition switch ON and attempt to use the hand-held tester. If the screen displays UNABLE TO CONNECT TO VEHICLE, a problem may be on the vehicle side or tester side.

    • If communication is normal when the tester is connected to another vehicle, inspect the DLC3 of the original vehicle.
    • If communication is still impossible 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.
    Fig 3: Connecting Hand-Held Tester (With CAN VIM) To DLC3
    G01442891Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. CHECK BATTERY VOLTAGE 

    Standard: 11 to 14V 

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