I recently added a garage door opener to my S40 that opens when you flash the high beams.  It was pretty simple.


Old garage door opener remotes run on 12 volts.  You can either leave the battery in the remote and hook a relay to the high beam or you can solder the button pressed and hook the +12 and ground from the battery connectors to the high beam circuit.  I did the latter.  

• Take apart the garage door opener.  Pull out the battery.
• Look at the solder pads circuit board behind the button.  Figure out which connections get shorted together to make the circuit work. Solder a wire across those connections.  You should probably disable, crush, remove the switch at the same time.
• Remove the battery connectors and solder wires in their place.  
• Test by connecting the battery to the wires.  Your door should open as soon as you power up the remote because you soldered the door button "pressed" in the earlier step.
• Wrap the remote circuit board in something that will keep the water out. A lot of folks use epoxy
• Go into the headlamp bucket and attach the +12 to the high beam and the ground to the single ground wire. Turn on the bike and flash the high beams.  The door should activate only when you flash the high beams.  If it runs as soon as you turn the bike on then you probably hooked it to the lo-beam circuit.
• Put it all back together.

I have a Marauder headlamp on my S40 but it should fit in the stock fixture also.

I have the horn activated model but sadly it sometimes malfunctions   .Maybe a short somewhere?