- 1). Choose a location for your horn on the roof of your car that is close to a place inside your car where you have room to mount the compressor. For instance, you can mount the trumpets on the center of your car's roof and the compressor on the frame between the doors of a four-door car or SUV.
- 2). Place the horn gasket at the location where you want to install the horn mounting bracket and line it up at whatever angle you wish. Use your marking pen or grease pencil to mark your roof at the point where each of the holes in the gasket is located and remove the gasket. There are two holes for the regular model and three in the LED model template.
- 3). Drill the front bolt mounting hole with a 5/16-inch bit. Drill the rear air inlet fitting hole with a 3/16-inch bit. Drill the side LED wires with a 3/8-inch bit if you have the LED light model.
- 4). Align the gasket holes with the holes you drilled. Thread the LED wires through the side LED hole into the interior of your car roof if you have the LED model. Place the rear of the horn assembly over the gasket and line up the holes with the gasket holes.
- 5). Place a washer on the front mounting hole of the horn mounting bracket and insert the mounting bolt through the hole. Thread the LED wires through the inner mounting plate if you are installing the LED model.
- 6). Line up the inner mounting plate on the inside roof of your car so that the bolt is flush with it and the rear hole is lined up with the rear hole that you drilled for the air inlet. Place a washer on the threaded end of the bolt inside the roof of your car and secure the bolt by threading a nut over it and tightening the nut against the washer and the inner mounting plate.
- 7). Place the flywheel over the rear air inlet hole on the inner roof mounting bracket. Place a washer over the flywheel. Insert the flexible inlet thread through the washer and flywheel. Thread the tube into the threaded receptacle on the inside bottom of the horn's outer mounting bracket.
- 8). Tighten the mounting nut and the flexible air inlet by hand or with a wrench. Do not over-tighten and make sure the inner bracket is positioned evenly and rests straight up against the inside roof of the car.
- 9). Drill a 5/16-inch mounting hole through the inner frame of your car where you want to mount the compressor. Choose a place close to the trumpets where there is enough room to mount it vertically and where it will not come into contact with anyone who is sitting near it. You may have to temporarily remove the interior trim to be able to mount the compressor onto the frame of your vehicle.
Insert the mounting post of the compressor into the slot at the rear of the compressor housing and push it in firmly so that it is seated in the slot. Insert the threaded end of the mounting post through the mounting hole. Slide a washer onto the end of the hole and fasten it to the inner frame of your car with the nut. Use a pair of pliers to position the washer and a wrench to fasten the nut if you cannot insert your fingers behind the inner frame of your car.
Insert the flexible air inlet into the outlet on the side of the compressor.
Loosen the two terminal screws at the bottom of the compressor unit housing. Skip to Step 15 if you want to use a separate switch for your Wolo Powerhouse horn. See Step 13 if you are hooking your Wolo up to a two-wire factory-installed horn or Step 14 if your horn has only one wire.
Disconnect the wires of a two-wire factory installed horn from the positive and negative terminals of the factory-installed horn compressor. Bend the exposed parts of the wires and hook each one around the respective terminal screw of the Wolo compressor. Tighten each terminal screw with a screwdriver.
Disconnect the wire from a single-wire factory-installed horn and hook the end around the positive (+) terminal of the compressor before tightening the terminal screw. Connect one end of a length of a 16-gauge wire to the negative terminal of the compressor and connect the other end of the wire to any clean and rust-free bolt on the car body to ground the compressor.
Mount the provided relay in a dry place near the compressor with the terminals facing downward if you want to use a separate horn switch. You can use a self-tapping metal screw to fasten it to the inner frame of your car. You can also mark the hole in the mounting lug and drill a mounting hole. Then, you can use a bolt, washer and nut to fasten it to your car.
Connect one end of a piece of 16-gauge or heavier wire to the top terminal of the relay (marked "87") and the other end to the positive terminal of your compressor. Connect one end of a piece of 18-gauge wire to the side terminal of the relay that is marked "85" and the other end to one horn switch terminal.
Connect one end of another piece of 18-gauge wire to the remaining horn switch terminal. Connect the other end of the wire to any clean and rust-free bolt to ground the switch.
Connect one end of a small piece of 16-gauge or heavier wire to the left-side "86" terminal and the other end to the bottom "30" terminal.
Connect one end of a piece of 16-gauge or heavier wire to either the "30" or the "86" terminal and the other end to the top terminal of a 20-amp fuse holder. (Solder the connections if the fuse holder requires soldering.) Connect another piece of the same grade of wire to the bottom terminal of the fuse holder and connect the other end of this wire to a 12-volt positive (+) terminal of your car's electrical system. Mount the fuse holder safely out of the way with tape or Velcro.
Attach a weather protection cover to each weather protection mounting bracket provided with the Powerhouse kit. Snap one bracket and cover assembly on to the front of each horn and insert and tighten the mounting screws in the center of each bracket.
Tape and secure any loose wires or vulnerable connections. Honk your horn with the factory horn or your new switch depending on how you installed it. If your horn sounds and you have a model without an LED light, you are ready to enjoy your new horn. See steps 22 and 23 for LED connection instructions.
Disconnect the brake light or engine light wire from your car's electrical system to use the LED of the Powerhouse as a brake or engine light. Connect the lighting wire to the bottom end of a fuse holder with a 3-ampere fuse installed. Connect the red LED wire of the Powerhouse to the top terminal of the fuse holder. (You may need to solder the wires to the fuse holder terminals if the holder does not have screw or quick-connect terminals.) Mount the holder to a safe and secure place with tape or Velcro.
Connect the black LED wire to any bolt on your car's frame to act as a ground. Lengthen it with 20-gauge wire if you do not have sufficient wire to reach a clean, rust-free and convenient bolt.
Tape and secure all connections. Turn on your engine and make sure the LED display at the back of the horn lights up when you turn it on or when you hit the brake depending on which option you chose for installation. You are now ready to use all features of your Wolo Powerhouse 120-decibel dual-trumpet horn with LED display.
Subscribe to our newsletter
Sign up here to get the latest news, updates and special offers delivered directly to your inbox.
You can unsubscribe at any time