LX150: Installing a BackOFF brake light flasher
I recently installed a BackOFF brake light flasher on my 2007 LX150. Although I didn't remember to take pictures untill I was almost done, I did snap a few at the end of key areas which should hopefully suffice for the purposes of this Tech Tip article.

Tools & Supplies you will need:
- 1 BackOFF brake light modulator
- Phillips Head Screwdriver
- Flat head screwdriver (fine blade, preferably)
- Needlenose pliers
- 1 roll 16 gauge wire (red) (no less than 6 feet)
- 1 roll 16 gauge wire (black) (" ")
- 1 roll 16 gauge wire (green) - Optional
- Wire stripper / crimping tool
- 14/16 gauge Male & Female connectors (blade-, bullet-style, etc.)
- electrical tape
- double-sided tape (included with BackOFF)
- Zip ties (aka, wire ties, tie bands, etc.)
- flashlight
- patience

Approx time to complete: 1.5-2.5hrs being very careful, taking your time, etc. - could be more, could be less. YMMV.

NOTE: There are 4 unique ways a BackOFF brake light flasher can be installed depending on what you want it to do. I wired mine according to do 4 short flashes and then "Steady On," (repeat). When you get to the appropriate step below, wire yours as you see fit using the BackOFF instructions as a guide if you wish to do a different mode than what I describe below.

Step 1. Before beginning the process, check to ensure that you have a functioning brake and tail light. If so, proceed. If not, troubleshoot that problem before beginning this project. Also, if you have a topcase, now would be a good time to remove it for the sake of allowing light to reach your work area behind the tail lamp lens.

Step 2. With the Vespa on its center stand, and preferably with a cool engine and exhaust, sit down on the floor behind the scooter and remove the 2 screws that hold the tail lamp lens in place. Carefully pull the lens toward you taking care not to lose the screws.

Step 3. Remove the bulb and wiring harness from the tail lamp assembly. If you've never done this before, it's achieved by turning the entire orange piece that holds the bulb about 1/4 turn to the left. You may meet some resistance - this is just due to the black O-ring sticking. Set the red lens aside in a safe place once these two are separated.

Step 4. Remove the bulb from the orange holder. To accomplish this, press IN, then TURN the bulb, and it will come out. Set the bulb aside.

Step 5. Disconnect the bulb's wiring harness from the scooter. You will see a triangular(ish) shaped plug connection between the orange holder and the scooter - this connection simply pulls apart. It is "keyed", so it can only go back together one way.

Step 6. Now remove the chrome plastic tail lamp trim piece still attached to the scooter. This is accomplished by removing the 2 Phillips head screws holding it in. Once you have it loose, take care not to let it rub against the paint too much, as there it sure to be some light dirt and dust behind it that will scratch your paint. Once removed, set the trim piece aside while taking care not to lose the screws. Now would be an excellent time to give the area a thorough cleaning with the spray detailer of your choice and a soft cotton terrycloth or microfiber towel.

Step 7. (I was going to make this step optional, but I really think it's necessary, so I'm adding it as a numbered step.) Remove both left and right turn signal assemblies. This is accomplished by removing 1 Phillips head screw (per side) and pulling the lens assembly out. If necessary, a fine blade flathead screwdriver may be appropriate to "encourage" the lens out, should it appear stuck. Take care not to scratch your paint. Once removed, pull all the way out and let dangle by their wires.

(Because there is not enough room behind the tail lamp assembly and lens to mount the BackOFF unit, you'll need to run wire to somewhere else on the scooter where it will be mounted.)

Step 8. Looking at where the existing wires come out the back of the scooter, you will see they come through a black rubber grommet. Using either your needlenose pliers or the fine blade flathead screwdriver, gently pry or pull this rubber grommet out of the hole it seals. Do not attempt to remove it completely from the wires - just leave it as-is - and pop it out of the hole.

Step 9a. Beginning with the Red 16 gauge wire, feed one end through the hole that the rubber grommet plugged. Continue advancing the wire into the body of the scooter. The goal here is to advance the wire so that it can be seen either through the holes where the turn signal lenses were or from underneath the scooter (laying on the ground, head partially under bodywork, looking up). For me, this was the longest and most tedious part of the process. In short, there's no guaranteed easy way to fish the wire through. It's very tight in there, and the wire's tendency will be to curl upwards towards the top of the scoot - you need it to go down. Don't give up at this step! This can be done, and once completed, you'll be 75% of the way home.

I found that I was able to first see the red wire by advancing a significant length of wire into the body of the scooter and then looking through the left-rear turn signal lens hole (the side opposite the exhaust). Once a small loop of wire was visible, I was able to grab ahold of it and pull it out the turn signal hole with needlenose pliers.

Step 9b. Once you have the red wire pulled through below, you'll need to achieve the same result with the black wire. There is an easier way, now!

Step 9b.i. Twist approximately 4-6 inches of black wire with the end of the red wire you've pulled through below. Now pull back on the red wire above (through the tail lamp hole) until both wires come out that hole.

Step 9b.ii. Untwist the red & black wires. You should now have just the black wire going through the hole, and the red wire that you spent all that time fishing through will be in a pile on the floor. Not to worry. Now pull several feet more of the black wire out through the hole in the back of the scooter.

Step 9b.iii. Now twist 4-6" of the red wire around the black wire close to the tail lamp hole in the back of the scooter - NOT at the end of the black wire! Pull on the black wire from below until the red wire is advanced through. Untwist them.

Step 9b.iv. You should now have both the black and red wires going through the hole in the back of the scooter and advancing down below the body work. There will most likely be significantly more red wire coming out the back of the scooter. The last step here is to even up the wire lengths by pulling on just the red wire (below) until the same amount remains at the tail lamp for each color. I think 6-12" will suffice for now.

Congratulations! The hardest part is over. Go relax for a few minutes and come back with a clear head. I know that last part was tedious. It's even worse to have to write it out than to just do it!

Step 10. Welcome back. You must now decide where you want to place the BackOFF module. I mounted mine to the inside of the body under the pet carrier. I placed it as far forward and as high up as I could - under the seat hinge. I chose this location because it will allow for easy disconnection and/or troubleshooting in the future without having to take the whole scooter apart again. Once you have chosen a location, pull the wires to that general area taking care not to pull them all the way through the tail lamp hole!

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Optional Step - I placed the long ends of the red and black wires (i.e., the end NOT coming out the back of the scooter) into the chuck of a battery-powered drill and spun them on low speed to create a "loom" of sorts. It's up to you whether to do this or not - I just thought it would help keep things neat once everything was buttoned up.

Step 11. Moving back to the rear of the scooter, it's now time to run the red and black wires through the hole in the black rubber grommet that the existing wires are passing through.

Step 12. Trim the red and black wires to the appropriate length with your wire cutters. 3-4 inches should be all you need at this point.

Step 13. Pick up the orange tail lamp bulb housing and wiring harness. You should see 3 wires going to it - Yellow, Black, and Black with a White stripe. The Yellow and the Black w/ White stripe should be side-by-side, and the (plain) black should go off to a different location on the orange housing. The Yellow wire is the tail lamp wire. The Black with White stripe wire is the BRAKE light wire. This is the one you should splice into. Cut the wire as close to the center as possible, as you don't have much extra length to work with.

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Step 14. Strip each side of the wire you just cut. About 1cm will do.

Step 15. Now add the connectors to the wires. I believe it is a good idea to crimp a Male connector to one side of the brake light wire and a Female to the other in the event you ever need to take the BackOFF out of the circuit. Attach the matching connectors to the red & black wires to the ones you just crimped to the brake light wire.

The brake light wire attached plastic (triangularish) connector will pair with the red wire, and the brake light wire attached to the orange bulb housing will pair with the black wire.

Step 16. Now carry out the same process at the other end of the red & black wires. Cut them to the appropriate length for where the BackOFF unit will be mounted, and strip the appropriate length of insulation off the wire to attach the Male/Female connectors. This is another area where I added Male to red and Female to black - it provides a quick and easy disconnect that will put the system back to stock, should you ever need to.

Step 17. Add the matching connectors to the BackOFF unit BEFORE you permanently place it with the included double-sided tape. The red 16ga wire you've run with connect to the red wire on the BackOFF. The black wire you've run will connect with the wire that is White with a Red stripe.

Step 18. Attach the black wire from the BackOFF unit to a "ground." Because of my mounting location, I chose one of the bolts that fastens the seat hinge. If you need to go further than what the black wire will reach, use the green wire and connectors

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Step 19. Connect all Male/Female connectors you've just added. Connect brake light harness to (existing) Vespa wires with grey "triangular(ish)" connector. The routing should go something like this:

Vespa wire loom (from tail lamp hole) --> grey connector --> Black wire w/ white stripe --> 16ga red wire --> (BackOFF) red wire --> BackOFF Unit --> White wire w/ red stripe --> 16ga black wire --> black wire w/ white stripe --> bulb housing.

External inline image provided by member with no explanatory text

Re-install brake light bulb in orange housing. Put key in ignition and turn to Auxiliary position. Pull brake lever - it should flash!

Step 20. If everything works correctly, turn key off and remove the brake light bulb. If not, check your connections (including ground) and try again. Once proper function has been verified, permanently mount the BackOFF unit using the included double-sided tape. Secure all wires to the frame with Zip Ties. Trim excess with wire cutters. Re-install all parts removed in the reverse order.

Congratulations! You're done, now go ride!!!
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