DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
INSPECT RADIO RECEIVER ASSEMBLY
CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MULTI-MEDIA INTERFACE ECU)
INSPECT MULTI-MEDIA INTERFACE ECU
AUDIO AND VISUAL SYSTEM (w/o Navigation System) - 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 assembly.
The radio receiver assembly 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 assembly is functioning, no sound, or only an extremely faint sound, can be heard.
WIRING DIAGRAM
INSPECTION PROCEDURE
| 1.INSPECT RADIO RECEIVER ASSEMBLY |
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
| Tester Connection | Switch Condition | Specified Condition |
| F55-6 (MUTE) - Body ground | Engine switch on (ACC), USB audio system is playing → Mode is changing | Above 2.5 V → Below 0.5 V |
Text in Illustration| *1 | Component with harness connected
(Radio Receiver Assembly) |
| OK | |
| |
| PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE ()
|
|
| 2.CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MULTI-MEDIA INTERFACE ECU) |
Disconnect the F55 radio receiver assembly and L40 multi-media interface ECU connectors.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
| Tester Connection | Condition | Specified Condition |
| F55-6 (MUTE) - L40-6 (MUTI) | Always | Below 1 Ω |
| F55-6 (MUTE) - Body ground | Always | 10 kΩ or higher |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 3.INSPECT MULTI-MEDIA INTERFACE ECU |
Reconnect the L40 multi-media interface ECU connector.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
| Tester Connection | Switch Condition | Specified Condition |
| L40-6 (MUTI) - Body ground | Engine switch on (ACC) | Above 2.5 V |
Text in Illustration| *1 | Component with harness connected
(Multi-media Interface ECU) |
| | REPLACE MULTI-MEDIA INTERFACE ECU ()
|
|
|
| OK | |
| |
| REPLACE RADIO RECEIVER ASSEMBLY ()
|
|
