Inspection Procedure

WARNING: This page is about a different car, the 2006 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

CHECK HARNESS AND CONNECTOR (FRONT CONTROLLER - HEADLIGHT BEAM LEVEL CONTROL ECU)

Disconnect connector 1H from the front controller.

Fig 1: Identifying Front Controller - Headlight Beam Level Control ECU Connector Terminals (1 Of 2)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the headlight beam level control ECU connector.

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

Fig 2: Identifying Front Controller - Headlight Beam Level Control ECU Connector Terminals (2 Of 2)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

STANDARD RESISTANCE CONDITION CHART

Tester Connection	Condition	Specified Condition
A21-7 - 1H-11	Always	Below 1
A21-7 - Body ground	Always	10 k or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - HEADLIGHT BEAM LEVEL CONTROL ECU)

Disconnect the headlight beam level control ECU connector and the skid control ECU connector.

Fig 3: Disconnecting The Headlight Beam Level Control ECU Connector And The Skid Control ECU Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

STANDARD RESISTANCE: WITHOUT VSC CONDITION CHART

Tester Connection	Condition	Specified Condition
A21-6 - A40-13	Always	Below 1
A21-5 - A40-24	Always	Below 1
A21-6 - Body ground	Always	10 k or higher
A21-5 - Body ground	Always	10 k or higher

STANDARD RESISTANCE: WITH VSC CONDITION CHART

Tester Connection	Condition	Specified Condition
A21-6 - A34-39	Always	Below 1
A21-5 - A34-40	Always	Below 1
A21-6 - Body ground	Always	10 k or higher
A21-5 - Body ground	Always	10 k or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (GENERATOR ASSEMBLY - HEADLIGHT BEAM LEVEL CONTROL ECU)

Disconnect connector B6 of the generator and connector A21 of the headlight beam level control ECU.

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

STANDARD RESISTANCE CONDITION CHART

Tester Connection	Condition	Specified Condition
B6-4 (L) - A21-8 (CHG-)	Always	Below 1

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig 4: Identifying Terminals Of Headlight Beam Level Control ECU Connector

OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE