7. Tighten the supplied 10mm bolt through the Air Horn Mounting Bracket on the driver’s side into the extruded U-nut.
8. On the passenger side, re-position the exhaust hanger so that its mounting hole is aligned over the hole on the Air Horn Mounting Bracket. Re-use the original inner frame bolt that held the exhaust hanger to now secure both the exhaust hanger and the bracket. Re-install the remaining exhaust hanger bolt in its original location and tighten.
9. Re-attach the brake line bracket in the original location, using the original bolt.
10. Re-attach the factory harness on the driver’s side by inserting the original fastener into the hole on the side of the Air Horn Mounting Bracket. Electrical and Air Connections
11. Route the air line to the compression fitting on the inlet of the solenoid valve – making sure that it is not near the exhaust or any moving parts. Attach the air line to the compression fitting on the solenoid.
12. Use zip ties to secure the loom holding the purple wire to the air line from where it exits the air tank, all the way back to the air horn.
13. Connect one of the wires from solenoid (it does not matter which) to ground using the short black ground extension wire with the blue ring terminal and the self-tapping screw. Attach the red female bullet connector, then slide one piece of heat shrink over the wire. Plug the two halves of the bullet connector together and position the heat shrink to cover both bullet connectors. Don’t apply heat yet - wait until after the entire system has been installed and successfully tested.
1. Your system comes with an easy-to-install wiring harness, designed to be installed behind the compressor with wires running forward and with the long purple wire running towards the rear of the vehicle. Do not cut wires to length until you are 100% sure of the length required for connections.
2. Locate the red power wire that was previously run to the battery area. Install supplied fuse holder on the end of this power wire by cutting the loop in the fuse holder and connecting a Ring terminal to one end. The ring terminal will be connected to the positive terminal of the battery. Install the 30-amp fuse provided after all other electrical connections are made.
3. Route the yellow and purple paired wires from the wiring harness through the grommet in the cab floor, (see Image K on next page)
4. Connect the yellow wire to a 12-volt, switched (turns on/off with key) power source.
5. Find a suitable location for the pushbutton and drill a 3/4” hole. Run the purple wire from behind and through the hole along with the supplied section of 18 gauge red wire. Slide the pushbutton retaining nut over both wires, then connect the purple to one terminal of the pushbutton and the red to the other terminal. Install the pushbutton into the hole and tighten the nut.
6. Route the 18 gauge red wire to a fused power source and connect.
7. Insert the 30-amp fuse into the fuse holder at the battery, start engine and test the compressor system by running the compressor to build up pressure in the air tank.
8. Once air pressure reaches the preset cut out pressure of your pressure switch, the compressor will shut off. Inspect all air line connections for leaks with soap and water solution sprayed directly onto fittings. If a leak is found: remove, re-seal and reinstall fittings as needed.
9. Once the tank is filled, test the air horns. Once you have confirmed proper operation, go back to air horn solenoid connections and apply heat to the heat shrink tubing. Be careful not to overheat and burn the wires.
Image K - Location of the two 12-volt wires for switched power (ignition) and your horn button, routed into cab through floor on passenger side.