Mute Signal Circuit between Radio Receiver and Multi-media Interface ECU

AUDIO / VIDEO: AUDIO AND VISUAL 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 sends a mute signal to the radio receiver.

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

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 is functioning, no sound, or only an extremely faint sound, can be heard.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT RADIO RECEIVER

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





Standard Voltage:





Text in Illustration

Text in Illustration:

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

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

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

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

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





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

Standard Voltage:





Text in Illustration

Text in Illustration:

NG -- REPLACE MULTI-MEDIA INTERFACE ECU Removal

OK -- REPLACE RADIO RECEIVER Removal