As luck would have it, two very useful but simple electrical mods - a turn signal beeper and an accessory power outlet - can get everything they need right there at the alarm connector. And the knee panel is just the place to mount them. This project, then, is actually these two mods in one.
I try to mod my scoot with as light a hand as possible:
* The mod does not overload or otherwise compromise the circuits it is tied in to.
* Factory wiring is not cut, spliced, or otherwise altered.
* Only easily replaceable scooter parts are cut.
* All added components and wiring are mounted and connected so as to withstand the vibration and dirt inherent in road service.
* The finished install is visually clean and compact, both inside and out.
I used the following parts. I got all my electrical parts from Radio Shack, so I'm including the Radio Shack part numbers (with links) and prices:
Piezo Buzzer, 273-068, $9.49
Accessory Power Outlet, 270-1556, $6.99
6-position Barrier Terminal Strip, 274-659, $2.39
1N4005 Diodes, 276-1104, $0.99 (for two)
1N4005 diodes are actually overkill for this application, but they're cheap, available, physically small, and they work fine. They'll take an inverse voltage of 600V (they'll only see 12V here), and they'll pass 1 amp (the buzzer only draws 10 mA.)
I also used:
6-32x½" machine screws (qty 4, for mounting the terminal strip)
#6 lockwashers (qty 4, also for the terminal strip)
6-32 nuts (qty 4, ditto)
#16 stranded wire (a few feet, included with the power outlet)
small wire ties (qty 4)
spade-type crimp terminals (qty 8.)
Crimp terminals are great for connecting stranded wire to screw terminals without the stray wire strands or loose mechanical connections you get when clamping stranded wire directly under screw heads.
Altogether, these materials totaled under $25. But, because I'd be cutting holes in the left knee panel, (and taking the "keep it factory" constraint to the extreme) I also ordered a new panel from Piaggio through my dealer. The part number is 577395000C. As I remember, that part cost something like $30. It's optional.
I tapped into the unswitched 12V for outlet power because I wanted to be able to connect a battery tender to the battery through the outlet while the scooter is parked and turned off. You could just as easily tap into the switched power if you want the outlet to be hot only when the scooter is on. The choice is yours.
All s appreciated.
Here's a sketch of the mod.
On the knee panel, mark the centers of the holes for the outlet and the buzzer, 1½ inch from each side, 1½ inch from the bottom.
Cut the two holes in the knee panel with a 1 inch hole saw.
Open both holes up to about 1-3/16 inch with an abrasive drum. I used a Dremel tool attachment.
Work slowly and trial fit as you go. You don't want to make these holes too big!
De-burr the finished holes with a sharp hobby knife.
Cut a small square clocking notch on the left side of the outlet hole. Use the rib on the outlet housing as a guide.
Mark the centers of the terminal strip mounting holes, using the terminal strip as a template.
Drill out the terminal strip mounting holes with a #28 drill bit.
Mount the buzzer, outlet, and terminal strip to the knee panel. The terminal strip mounts with the 6-32 hardware.
Mount the diodes "bands together."
Wire the components to the terminal strip per the sketch above. Use crimp terminals at the screw connections.
Tap into the alarm connector as shown on the sketch. Stranded wire works best here if it's first tinned with solder and slightly mashed.
Secure the wires to the plug and to the plug harness with wire ties. Return the harness to its clip behind the knee panel.
Secure the knee panel to the leg shield. Black screws would really make it look finished.
Last edited by Cincinnati John on Sat Oct 10, 2009 2:49 pm; edited 12 times in total