Disconnect the F19 radio receiver assembly connector.

This circuit sends the microphone signal from the map light assembly (telephone microphone assembly) to the radio receiver assembly.

It also supplies power source from the radio receiver assembly to the map light assembly (telephone microphone assembly).

This circuit is used when an incoming cellular phone voice in the "Bluetooth" handsfree system is received.

The circuit is necessary for the Automatic Sound Levelizer (ASL) built into the stereo component amplifier assembly.

Speed signals are received from the combination meter assembly and used for the ASL.

The ASL function automatically adjusts the sound volume in order to clear audio quality even when vehicle noise increases (as vehicle noise increases, the volume is turned up etc.).

Each audio system component connected to the AVC-LAN (communication bus) transfers the switch signals by the audio visual communication local area network.

If a short to +B or short to ground occurs in this AVC-LAN, the audio system will not function normally as communication is stopped.

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.

This circuit sends a signal to the stereo component amplifier assembly to mute noise. Because of that, the noise produced by changing the sound source ceases.

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 stereo component amplifier assembly is functioning, no sound, or only an extremely faint sound, can be heard.

The No. 1 stereo jack adapter assembly sends the sound data signal of an external device to the multi-media interface ECU through this circuit.

The No. 1 stereo jack adapter assembly sends sound signal from an external device to the radio receiver assembly through this circuit.

The sound signal that has been sent is amplified by the stereo component amplifier assembly or radio receiver assembly, and then is sent to the speakers.

The multi-media interface ECU sends sound signals to the radio receiver assembly through this circuit.

If there is an open or short in the circuit, sound cannot be heard from the speakers even if there is no malfunction in the stereo component amplifier assembly, radio receiver assembly or speakers.