BackOFF brake module install help

[CraigRegs]

Oh goodie, an electrical issue...

I acquired another '15 and am installing a BackOFF XP brake light flasher. I have one on my current '15 so I referred to it when doing this install, but the new one isn't behaving properly. Summary of the install: You cut a power lead to the brake light (yellow wire) and wire the BO module in-line. Red goes to the upstream (power) end, one of two other wires goes to the downstream (lights) end, depending on the flash pattern you want. Red with white stripe flashes 4 times, then holds steady. White with red stripe, continuous flash.

Current install uses the Red/Wh wire and flashes 4 times, then holds steady. On the new install, regardless of which wire I connect, I get a blink-flicker-blink-flicker-etc. pattern. I spoke with BO tech support and even sent the module back for them to test. They say it checks out ok and sent it back. I have referred to the current install numerous times and have wired things exactly the same. No bueno.

Any ideas?

[CraigRegs]

Some additional info from the multimeter:
Meter inline with just the brake wire, no module, shows about 2v without the lever or pedal pressed. Pulling the lever shows 12v, as expected.
With the module inline, the meter reads 0 with no lever or pedal, pulses up to about 10V with each flash of the brake light.

Is something else feeding 2V into that yellow wire?

[extrememarine]

The only suggestion I have is to bring it to Tech Day at Geek's and let Tim figure it out...

[CraigRegs]

If I don't hear anything further from here, or from my second inquiry to Signal Dynamics, that sounds like a good idea.

[DesignFlaw06]

Some additional info from the multimeter:
Meter inline with just the brake wire, no module, shows about 2v without the lever or pedal pressed. Pulling the lever shows 12v, as expected.
With the module inline, the meter reads 0 with no lever or pedal, pulses up to about 10V with each flash of the brake light.

Is something else feeding 2V into that yellow wire?

Where is your ground hooked up to? Is there anything else hooked up to the brake light? Or what other accessories are hooked up to the bike?

I don't have a Gen 3 schematic, but usually a brake switch just switches between 12V and open. The 2V could be from where you're measuring ground.

Did you cut the yellow wire far enough back where it is feeding both bulbs and not just one? Does it behave differently if the bike is just on instead of running?

[raYzerman]

I just looked at the instructions from the link you provided....... it says it will not work with LED brake lights. In that case you need the XP model... is that one definitely the one you have..... did the PO change the bulbs to LED perhaps?

[CraigRegs]

Addressing Ray's Qs first:
- It is the BackOFF XP model.
- Bike has incandescent bulbs.

Tim's Qs:
- Ground is hooked up to ground buss of my Blue Sea fuse block under the seat which is wired direct to battery. This fuse block and wiring to the battery are identical to my old bike.
- As far as I can tell, there are no other mods to the brake lights or wiring.
- I cut the yellow in the same location as on the old bike; under the front of the passenger seat, on the left side, right between the two aluminum brackets where the seats latch. With the wire cut, running lights illuminate, but neither brake light shines (duh). Bridging the cut wire lights up both bulbs with the lever or pedal. With the module in-line, both bulbs light up with the lever or pedal, but the pattern is as described previously.
- The flash pattern is different with the bike running as opposed to off. With either wire (R/wh or Wh/R), it holds for a couple seconds, then flashes slowly, flickering (rather than steady) when it's on, then holds again and may begin flashing again. Probably not a random pattern, but nothing near what is advertised. Applying some throttle tends to make it go steady with a flicker, but then it flashes some and may hold then flash.

[raYzerman]

I vote module FUBAR, return for warranty....

[Festus]

If you switch the devices from one bike to another does the problem move or stay with the bike?

[DesignFlaw06]

It could still be a grounding issue. As a "bench test", I would bypass the bike wiring for the brake signal and ground. Just hook directly to the battery and see if it behaves correctly or not. Try to rule out the bike as much as possible.

[raYzerman]

There is no ground wire, only two wires.... cut the yellow and red hooks to upstream, and white to downstream (the bulbs). If all rear lights are working then the common ground is likely OK. You could tap into the black and take it directly to ground to assure yourself it's good. If that's good then the module is faulty IMHO...... and I'd be talking to the Signal Dynamics folks, can't hurt to ask....

There is a 6-way connector (5 used) behind the airbox for the rear lighting... maybe unplug and see if it needs a refreshed connection??

[Festus]

Maybe you missed it, he's already talked to them, already sent it back to them, and they have verified it's not faulty.

[DesignFlaw06]

There is no ground wire, only two wires.... cut the yellow and red hooks to upstream, and white to downstream (the bulbs). If all rear lights are working then the common ground is likely OK. You could tap into the black and take it directly to ground to assure yourself it's good. If that's good then the module is faulty IMHO...... and I'd be talking to the Signal Dynamics folks, can't hurt to ask....

There is a 6-way connector (5 used) behind the airbox for the rear lighting... maybe unplug and see if it needs a refreshed connection??

He has the XP, he just linked to the wrong page. There are 4 wires. 12V In, Ground, Mode 1, and Mode 2. As Signal Dynamics has already inspected it, my suspicion is that it is something to do with the bike's wiring.

Swapping units between bikes is diagnostically the best bet, but may not be feasible depending on how it is hooked up. My other question is what else is hooked up to the fuse block? And I guess does the brake light behave correctly without the module installed?

[raYzerman]

OK I missed the part about SD getting it back and testing it (where was that said?)....... take the ground to a direct ground and eliminate the Fuseblock... at the six-way I mentioned, the black wire is ground for all the rear lighting.

[Festus]

OK I missed the part about SD getting it back and testing it (where was that said?).......

Post #1?

I spoke with BO tech support and even sent the module back for them to test. They say it checks out ok and sent it back. I have referred to the current install numerous times and have wired things exactly the same. No bueno.

[CraigRegs]

Got it to work after hooking up various wiring combos. Using the Wh/R to feed the BO unit, and R/Wh out to the brakes provided the 4 flashes and hold.

Whatever. It works...

[FJRPittsburgh]

Got it to work after hooking up various wiring combos. Using the Wh/R to feed the BO unit, and R/Wh out to the brakes provided the 4 flashes and hold.

Whatever. It works...

Evidently trial and error is better than just error alone. Congrats!