Diagnosis System

WARNING: This page is about a different car, the 2007 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.

DESCRIPTION
Retractable hardtop system data and Diagnostic Trouble Codes (DTCs) can be read using the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the intelligent tester to check for malfunctions and perform repairs.

CHECK DLC3

HINT:

The vehicle's ECU uses ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.

Fig 1: Identifying DLC3 Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

Symbols (Terminals 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

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 intelligent tester to the DLC3, turn the ignition switch ON and attempt to use the tester. If the screen displays the message UNABLE TO CONNECT TO VEHICLE, 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 is probably in the tester itself. Consult the Service Department listed in the tester's instruction manual.

Fig 2: Connecting Intelligent Tester To DLC3
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK INDICATOR LIGHT

Prepare the vehicle by satisfying all of the following conditions:
1. Vehicle speed is 5 km/h (3 mph) or less
2. Luggage door opener main switch is ON
3. Tonneau cover switch is ON (Only when roof is open)
4. Luggage courtesy switch is ON

Operate the sliding roof using the control switch and check that the indicator light operates as described in the table below.

Fig 3: Identifying Luggage Door Opener Main Switch

OK:

SLIDING ROOF SPECIFICATIONS

Sliding Roof	Indicator Light
Half open	Illuminates
Conditions for system activation not satisfied* 1	Blinks*2
Fully open or fully closed	Turns off
HINT: 1: If the system activation conditions are not met, the indicator light will blink. If it does not, the indicator light may have a malfunction. 2: Only when the control switch is being pressed.