Section 10-03: Speed Control System | 1993 Mustang Workshop Manual |
The vacuum dump valve provides an additional safety feature in the system. Normally, when the brake pedal is depressed, an electrical signal from the stoplamp switch to the amplifier will turn off the system. In addition, the vacuum dump valve will mechanically release the vacuum in the servo when the brake pedal is depressed. This releases the throttle independently of the amplifier control.