Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

PERFORM ACTIVE TEST USING TECHSTREAM

Connect the Techstream to the DLC3
Turn the engine switch on (IG)
Turn the Techstream on.
Enter the following menus Body Electrical / Body No 5 / Active Test

Check the operation

Body No. 5 (Front Controller)

ACTIVE TEST - BODY NO. 5 (FRONT CONTROLLER)

Tester Display	Test Part	Control Range	Diagnostic Note
Light Head (High)	Headlight (HI) operation	ON/OFF	-

OK: Headlight (HI) comes on.

NG: Go to step 2

OK: REPLACE HEADLIGHT ASSEMBLY (See HEADLIGHT ASSEMBLY )

CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - FRONT CONTROLLER)

Disconnect the B2 or B12 headlight assembly connector.
Turn the light control switch to the ON (HEAD) position.

Measure the voltage according to the value (s) in the table

Standard Voltage

STANDARD VOLTAGE SPECIFICATION

Tester Connection	Condition	Specified Condition
B2-4 (B) - Body ground	Light control switch in HEAD	11 to 14 V
B12-4 (B) - Body ground	Light control switch in HEAD	11 to 14 V

Fig 1: Identifying Headlight Assembly Connector B2 Or B12 (Front Controller)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 4

OK: Go to next Step

CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - BODY GROUND)

Disconnect the B2 or B12 headlight assembly connector

Measure the resistance according to the value (s) in the table.

Standard Resistance

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
B2-3 (E) - Body ground	Always	Below 1 Ω
B12-3 (E) - Body ground	Always	Below 1 Ω

Fig 2: Identifying Headlight Assembly Connector B2 Or B12 (Body Ground)

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE HEADLIGHT ASSEMBLY (See HEADLIGHT ASSEMBLY )

CHECK HARNESS AND CONNECTOR (FRONT CONTROLLER - HEADLIGHT ASSEMBLY)

Disconnect the 2G front controller connector
Disconnect the B2 or B12 headlight assembly connector.

Measure the resistance according to the value (s) in the table.

Standard Resistance

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
2G-4 - B2-4 (B)	Always	Below 1 Ω
2G-4 - B12-4 (B)	Always	Below 1 Ω
2G-4 or B2-4 (B) - Body ground	Always	10 kΩ or higher
2G-4 or B12-4 (B) - Body ground	Always	10 kΩ or higher

Fig 3: Identifying 2G Front Controller Connector

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE FRONT CONTROLLER (MULTIPLEX NETWORK BODY ECU)