Here's how to install a Back-Off wig wag brake light modulator. You'll have to excuse the extra connectors not pointed out in the photos as my personal installation has more going on behind the scenes. But, use the following diagram and steps for installing it just for the factory brake lights.
- wire strippers
- wire cutters
- small flathead screwdriver
- 16-18 butt connectors x 4
- 16-18 wire taps
- 18" length of red(or white w/black stripe)16 or 18 guage wire
- exacto knife
- #33 electrical tape
Ok, first of course you'll need to remove the bottom rear body panel to get access to the taillight wiring. There's two plastic snap rivets that hold it in place on the bottom of either side. Remove those then slightly push in on the sides of the panel closest to the rear side panels and pull down and out. If it doesn't budge, try pushing forward a bit while pulling down and inward on the sides. The trick is not to force it as the 90 degree hooks that fit into the slots on the side panels are fragile and prone to breaking. So take your time removing it.
The following diagram is a rudimentary drawing of how it hooks up to the factory wiring for mode 2 (wig wag flash, combined flash, then steady on). If you want mode 1 which is a repeat of the wig wag and combined flashing continuously until you let off the brake handle, then use the solid red wire in place of the orange wire in the diagram.
It's easy to hook up if mounting the module on the right of the bike as that places the wires coming out of it towards the rear. Once you have removed the cover, use the exacto knife to cut the plastic tubing bundling the wires for each brake light socket to expose more of the wiring. Then, cut the white wire with black stripe on each of the sockets about 3" away. Tape off the end of the wire coming out of the harness for the left brake light socket as it won't be used.
Strip the white wire with black stripe coming out of the harness for the right brake light and connect it to the orange (Mode 2) or red (mode 1) wire on the module, depending on which mode you want, using one of the butt connectors.
Then, using the wire tap, connect the black wire from the module to the black wire with white stripe on the right taillight socket.
Now, strip one end of the 18" length of wire and connect it to the white wire with red stripe from the module using a butt connector. Run the wire behind the center metal bracket over to the left brake light socket. Strip the white wire with black stripe on the socket and connect one side of butt connector. Then, see how long you really need it then cut, strip and connect it to the other side of the butt connector.