Driver Controls and Instruments Cruise control and PTO governor are controlled with two switches. An ON/OFF switch allows the driver to select cruise control or to drive using the foot throttle. A spring-loaded SET/RESUME switch allows the driver to select the cruise speed or to resume the cruise speed after slowing down. The power takeoff mode of operation is also controlled with the cruise control switches, when the vehicle is sta- tionary. The engine speed can be set in the 800 to 1600 rpm range by placing the ON/OFF switch in the ON po- sition, then pressing the SET/RESUME switch when the desired rpm is reached. See Chapter 4 for detailed op- erating instructions.
f601424a 10/01/98 Parking Brake Control Valve Knob Fig. 3.8, Interrupt Switch A diamond-shaped knob in the control panel operates the parking brake control valve. See Fig. 3.9 . When the knob is out, the truck’s spring parking brakes are ap- plied. When the knob is in, the parking brakes are re- leased. Before the parking brakes can be released, air pressure in either brake system must be at least 65 psi (447 kPa). lights will come on and stay on as long as the problem exists. If the yellow engine check light comes on while driving, some engine features will not work, but the vehicle can still be driven.
If the red engine stop light comes on while driving, and if the engine will not accelerate, pull off the road and shut down the engine. In either situa- tion, have the problem repaired as soon as possible. See Group 54 in the Cargo Workshop Manual for troubleshooting procedures. See Chapter 7 for instructions on the use of the park- ing brake valve. 3.6