Dimmer Signal Circuit (TO 12/2010): Procedure

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT BODY ECU

Disconnect the radio receiver assembly connector.

Fig 1: Identifying Radio Receiver Assembly Connector Terminals
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
E34-20 (ADIM) - Body ground	Ignition switch ON, automatic light control sensor covered by hand, and light control switch tail or head position	11 to 14 V

TEXT IN ILLUSTRATION

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

NG → See step 3

OK: Go to next step

INSPECT RADIO RECEIVER ASSEMBLY

Disconnect the radio receiver assembly connector.

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

Fig 2: Identifying Radio Receiver Assembly Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

FOR 12 SPEAKERS

Tester Connection	Condition	Specified Condition
E31-20 (GND) - Body ground	Always	Below 1 Ω

FOR 9 SPEAKERS

Tester Connection	Condition	Specified Condition
E32-7 (GND) - Body ground	Always	Below 1 Ω

TEXT IN ILLUSTRATION

*A	for 12 Speakers
*B	for 9 Speakers
*a	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 body ECU connectors.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
D6-16 (ACAN) - E34-20 (ADIM)	Always	Below 1 Ω
E34-20 (ADIM) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → REPLACE BODY ECU

REPLACE RADIO RECEIVER ASSEMBLY. Refer to REMOVAL