Muting Signal Logic

All muting signals are passed through the GA-Net II bus. The audio unit determines the muting logic and what audio source has priority to use the speakers.

If the HandsFreeLink (HFL) is in use, a signal is passed through the audio unit to tell the navigation unit that the HFL is in use. The navigation unit temporarily disables the voice control system and suppresses voice guidance commands. In addition, the audio unit suppresses the output from the radio, XM radio, disc player, or other audio accessories. When the navigation system sends out a voice guidance command, the front speakers are muted, and the navigation voice is heard from the center speaker. When the voice control system is in use, all of the speakers are muted, and the navigation voice prompts are heard from the center speaker. Signals sent on the bus also control turning on the external amplifier when the audio unit is off.