Diagnosis System

Active torque control 4WD system data can be read in the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the Techstream to check for malfunctions and perform repairs. Therefore when there seems to be a problem with the active torque control 4WD, use the Techstream or SST to check and troubleshoot it.

1. The ECU uses CAN (ISO11898-1) and ISO9141-2 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO9141-2 format. Verify the conditions listed in the table below.
   Fig 1: Identifying DLC3 Terminals

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   TERMINAL DESCRIPTION CHART
   
   

   Symbol (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	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	6 kΩ or higher
   CANL (14)-BAT (16)	LOW-level CAN bus line	Ignition switch off(1)	6 kΩ or higher
   (1) 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 to the DLC3, turn the ignition switch to ON 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 of 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 instruction manual.

1. When a problem occurs in the active torque control 4WD system, the 4WD warning light on the combination meter comes on to inform the driver of the problem.
   Fig 2: Identifying 4WD Warning Light

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002