Muting Signal Logic

The muting signal is used to ensure that the navi voice prompts are processed correctly if the radio is on or off. The navigation unit uses the voltage on the mute wire to determine if the audio is ON or OFF. If audio is ON (+12 V), the navigation unit will immediately output (300 ms) its audio upon muting. If audio is OFF (open), the navigation unit will wait 2.0 second until the audio "wakes-up." So if the mute line is open and the audio was ON, there would be a 1.7 second longer delay for the navigation audio output to be heard. The average customer would probable not notice the difference.