INSTRUMENTS AND CONTROLS 79 The following optional switches, listed in alphabetical order, may appear on Panel D, shown on “Panel D”, page 54. • Accessory Switch (Battery Power) – This switch may be used to power optional accessory equipment that requires battery voltage, with the key switch turned OFF. • Accessory Switch (Ignition Power) – This switch may be used to power optional accessory equipment that requires ignition voltage, with the key switch turned ON. • Air Suspension Control Switch – This switch exhausts the air from the air bags of the suspension. It may be used when coupling or uncoupling trailers.
CAUTION When preparing to connect a tractor to a trailer, make sure that the height of the 5th wheel matches the height of the underside of the trailer. Failure to do so will result in the trailer being improperly connected. After the trailer has been coupled and the trailer landing gear has been raised, make sure that the 5th wheel jaws have properly engaged the trailer king pin, and there is no gap between the 5th wheel plate and the bottom of the trailer.
CAUTION DUMP BODY: Always exhaust the air from the bags before raising the dump body to protect the air bags and improve chassis stability while dumping. If the dump body is raised while the air suspension is pressurized, damage to the air bags may result.
CAUTION Do not drive the vehicle with the air bags exhausted. Repressurize the air bags before driving the vehicle. Note: Engine speed and road speed will automatically be limited if the vehicle is moved with the air bags exhausted. For information concerning trailer coupling and uncoupling, refer to the OPERATION section of this manual.
