Message Center Warning Chime
WARNING: This page is about a different car, the 2004 Mercury Monterey and 2004 Ford Freestar. However, it is still accessible from the selected car via links, so may be relevant.
The message center warning chime will accompany any initial warning message display, as well as any repeated initial warning message. As the message center is an integral part of the instrument cluster, the interaction between the message center and the chime function is also integral to the instrument cluster.
The message center switch tone sounds when any switch on the message center is pressed. The message center switches are supplied with a 5-volt reference signal from the instrument cluster. When a switch is pressed, it completes a circuit through a specific resistor in the switch assembly and back to the instrument cluster. The instrument cluster determines that a switch has been pressed when a voltage is returned to it.