The radio receives battery voltage at all times on circuit 640 through fuse E1-E2 in order to keep the clock and preset memory alive when the ignition is in the OFF position. The radio is grounded through circuit 351. When the ignition is in the ACCY or RUN position, the following actions occur:

The radio control switch controls the volume, the station frequency, and the tape functions. The radio control switch receives power through circuit 43. When one of the radio control switches is pressed to the desired function, a network of series resistors allows a different volage output through circuit 1796 to the radio.