Cellular Phone: Description and Operation

Battery voltage is supplied at all times through fuse 34 to the transceiver and through fuse 15 to the cigarette lighter relay. When the ignition is in ACC (I) or ON (II), battery voltage is supplied from fuse 8 to the cigarette lighter relay coil. The coil is grounded at G401. The coil then energizes, supplying battery voltage through the BRN/YEL wires to the transceiver. The transceiver is grounded at G551.

You can switch the transceiver to the radio speakers for hands-free phone operation. (A "mute" input to the radio cuts OFF the radio signals to the speakers if the radio is ON.)