Normal Operation
WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
The subwoofer speakers are powered from a separate subwoofer amplifier. The clip detection circuit 7-MD19 (YE/RD) carries out 2 functions: to turn the subwoofer amplifier on, and to indicate to the audio unit when the subwoofer output distortion signal reaches a damaging level. The audio unit then reduces the audio output signal to the subwoofer amplifier.