Dimmer Signal Circuit (From 8/2009): Procedure

INSPECT MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

Disconnect the radio receiver assembly connector.

Fig 1: Identifying Radio Receiver Assembly Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard Voltage

Tester Connection	Condition	Specified Condition
G9-20 (ADIM) - Body ground	Engine switch on (IG), automatic light control sensor covered by hand, and light control switch tail or head position	11 to 14 V

TEXT IN ILLUSTRATION

*1	Front view of wire harness connector (to Radio Receiver Assembly)

NG → See step 3

OK: Go to next step

INSPECT RADIO RECEIVER ASSEMBLY

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

Fig 2: Identifying Radio Receiver Assembly Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Condition	Specified Condition
G7-20 (GND) - Body ground	Always	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Front view of wire harness connector (to Radio Receiver Assembly)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → See step 4

CHECK HARNESS AND CONNECTOR

Disconnect the radio receiver assembly and main body ECU (multiplex network body ECU) connectors.

Fig 3: Identifying Radio Receiver Assembly And Main Body ECU (Multiplex Network Body ECU) Connectors
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard Resistance

Tester Connection	Condition	Specified Condition
F14-22 (ACAN) - G9-20 (ADIM)	Always	Below 1 Ω
G9-20 (ADIM) - Body ground	Always	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Front view of wire harness connector (to Radio Receiver Assembly)
*2	Front view of wire harness connector (to Main Body ECU (Multiplex Network Body ECU))

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → See step 5