Mute Signal Circuit Between Radio Receiver and Multi-Media Interface ECU

AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM (w/o Navigation System): Mute Signal Circuit between Radio Receiver and Multi-media Interface ECU
- Mute Signal Circuit between Radio Receiver and Multi-media Interface ECU

DESCRIPTION

The multi-media interface ECU assembly sends a mute signal to the radio receiver assembly.

The radio receiver assembly controls the volume according to the mute signal from the multi-media interface ECU assembly.

The mute signal is sent to reduce noise and popping sounds generated when switching modes.

If there is an open in the circuit, noise can be heard from the speakers when changing the sound source.

If there is a short in the circuit, even though the radio receiver assembly is functioning, no sound, or only an extremely faint sound, can be heard.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
After replacing the radio receiver assembly of vehicles subscribed to pay-type satellite radio broadcasts, XM radio ID registration is necessary (w/ SDARS System).

PROCEDURE

1. INSPECT RADIO RECEIVER ASSEMBLY

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





Standard Voltage:





Text in Illustration





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

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Problem Symptoms Table

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

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

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. INSPECT MULTI-MEDIA INTERFACE ECU ASSEMBLY

(a) Reconnect the multi-media interface ECU assembly connector.

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





Standard Voltage:





Text in Illustration





NG -- REPLACE MULTI-MEDIA INTERFACE ECU ASSEMBLY Removal

OK -- REPLACE RADIO RECEIVER ASSEMBLY Removal