Circuit Description
WARNING: This page is about a different car, the 2005 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.
The multi-display controller sub-assy sends a sound signal to the radio and navigation assy through this circuit.
The sound signal that has been sent is amplified by the stereo component amplifier assy, and then sent to the speakers.
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 assy or speakers.