AIR SUSPENSIONS AND HWH - HWH Corporation

The following diagrams represent the two different positions of the pilot dump valve, travel and dump.2-3.2 HWH pilot dump controls are part of the system control box or control panel. There will be a +voltage output for dump and travel. With a touch panel controlled system, each output will be fused. Witha 200 series joystick leveling system, both outputs are protected with the main panel fuse. HWH supplies aharness to connect to the pilot control valve. This harness has three wires in it and terminates into a 4 pinUML connector. The three wires are a black wire labeled 9300 for the dump signal, a black wire labeled9301 for the travel signal and a white wire for ground. One end pin has no wire, the next wire is the whiteground wire, the next wire is the black 9301 travel wire and the other end pin is the black 9300 dump wire.Refer to system electrical connection diagrams for specific control box or panel connections, fuselocations and led information where applicable.2-3.3 Pilot dump operation. Each different type of control system operates the pilot dump system a littledifferently. One thing that is consistent between all of the systems is that the ignition must be on and thepark brake must be set for the pilot dump system to dump the air. Another consistent feature is when theignition is on and the park brake is off, there is a + voltage signal to the travel side of the pilot controlvalve.There are several types of pilot dump controls for past or present, manual and automatic systems.1.) There is a rocker switch panel that can be used with or without any leveling system. The panel onlyhas a fuse and a rocker switch. With the ignition on and the park brake set, push the rocker to “AIRDUMP”. This will shift the pilot control valve to the dump position and the air will dump from the airbags. With the ignition on, push the rocker switch to “TRAVEL”. This will shift the pilot control valve tothe travel position. The air bags should start to fill and the vehicle should return to ride height. If theignition is on and the park brake is released, the pilot control valve will shift to the travel position.Page 6 – 22JUL09