Mute Signal Circuit between Radio Receiver and Multi-media Interface ECU (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 RADIO RECEIVER ASSEMBLY

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

Fig 1: Identifying Radio Receiver Assembly Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Voltage

Tester Connection	Condition	Specified Condition
E35-6 (MUTE) - Body ground	Ignition switch ACC, USB audio system is playing → Changing modes	Above 3.5 V → Below 1 V

TEXT IN ILLUSTRATION

*a	Component with harness connected (Radio Receiver Assembly)

NG → See step 2

OK → See step 4

CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MULTI-MEDIA INTERFACE ECU)

Disconnect the radio receiver assembly and multi-media interface ECU connectors.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
E35-6 (MUTE) - E41-6 (MUT1)	Always	Below 1 Ω
E35-6 (MUTE) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

INSPECT MULTI-MEDIA INTERFACE ECU

Reconnect the multi-media interface ECU connector.

Fig 2: Identifying Multi-Media Interface ECU 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
E41-6 (MUT1) - Body ground	Ignition switch ACC	Above 3.5 V

TEXT IN ILLUSTRATION

*a	Component with harness connected (Multi-media Interface ECU)

NG → See step 5

OK → See step 6

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE
REPLACE MULTI-MEDIA INTERFACE ECU. Refer to REMOVAL
REPLACE RADIO RECEIVER ASSEMBLY. Refer to REMOVAL