Radio, Stereo, and Compact Disc: Description and Operation

AUDIO SYSTEM
See Mazda truck wiring diagrams.

Principles of Operation

The audio unit can be powered up when the key is in RUN, ACC, or START. The audio unit provides audio signals to the speakers, thus producing sound. The audio unit directs the audio signals to the speakers through separate positive and negative circuits for each of the 4 audio channels: LH front, RH front, LH rear, and RH rear. The audio unit provides internal circuit protection for shorts to ground and shorts to battery.
The subwoofer speaker (Audiophile only) is powered by a separate subwoofer amplifier. The enable/clip circuit carries out 2 functions: to turn on the amplifier, and to indicate to the audio unit when the subwoofer output distortion signal reaches an excessive level. The audio unit then reduces (clips) the audio output signal to the amplifier.
The audio input jack allows for a portable MP3 player to be connected to the vehicle audio system. When a portable MP3 player is connected, audio from the MP3 player can be played through the vehicle speakers.