Ducati Monster Forum

I just installed a Motodynamics integrated taillight, but the brake indicator is not functioning, back or front levers.  Admittedly it was also not working with the Clear Alternatives light that was on before, but I thought the light itself was broken, hence replacing it.

Any ideas on where to look to troubleshoot this?

Also, there's an extra wire coming out of the harness which I am not sure what it's for, and it's not included on the install sheet . . . it's the connection I'm holding in the bottom left of the photo, what is its purpose?


(http://i91.photobucket.com/albums/k285/DanteFazio/photo-4.jpg)

ummmmmmmmmm, thats the brake light wire....... [bang] [clap]

what youve got wired up now are the signals....
that lead plugs into the lightbulb lead/ brakelight lead on clear alternatives, etc...

....basically thees 3 circuits, whether stock or clear alternatives....
Left, Right, and Running light/ Brake light....
need to find the plug end on your clear alternatives for the brakelight...
just plugged right into the factory socket on mine...

see the brakelight/ running light plugs in the center....?
factory fitting.....
perhaps yous is just bare wire....

(http://i34.tinypic.com/30adgs3.jpg)

Well that's what I suspected, but what I'm confused about is I followed the installation directions, and the turn signals function properly.

The Clear Alternatives light was installed when I got it, so if the harness was modified I wouldn't know.

So I should just figure out which one of those circuits corresponds to the running light and it'll go into that socket?  

yup......
its pretty obvious by physically looking at the unit....
left to left side, right to right, center is brake/ running....

hmmm and the more i think about it, i think they share common ground,
so each signal has one connection and the ground goes to the brake....
looks like it in my pic of the clear alternatives, but of course yours may be different...
been a while since i did mine, have to pull the seat and look to refresh my memory...

It seems like you've got the L-spades mixed up?

The thing you're holding in your hand is the license plate light rubber bulb holder.

Here's the install schema I followed, I feel like I'm missing something.

(http://i91.photobucket.com/albums/k285/DanteFazio/Picture3-1.png)

This from the site as well:

Park/Brake:
1. Unplug 3 connections from back of
factory tail light

2. Connect to LED tail light with the
following configuration:
Black - Black
Grey/Red - White
Yellow - Red

Note: Color may differ on various models

in your pic, are your red and yellow leads reversed......?

I don't think so, the yellow stock wire seems to go to the red Moto wire.  The stock wire is not entirely red, it's red/gray.

Not according to MotoDynamic, but according to us :)
Try reversing the two leads = grey/red to red and yellow to white. $10 says it'll work right [thumbsup]

And that's why I keep comin back here  [thumbsup]

I'll try that momentarily.

No dice, didn't have any affect.  I did try another combination but that turned the running light off entirely.

I'm out of ideas. You probably have to get in there with a test tool to find out if you have a broken connection elsewhere. Unless, of course, you can find a broken fuse....

Seems like it's time to find a test light and start poking around. Of the 3 L-spades, one is ground, 1 is always on, and one will only light up when the brake switch(es) are closed. Seems like you might have a break in your wiring.

It's probably not a fuse though. IF it was the tail light wouldn't come on at all.

I had a similar problem that just happened to coincide with the installation of a CA light. The nub between the front brake handle and the light switch wasn't moving very well. The light was always on. I put some lubricant in there and it fixed it up.

I'll check my wiring, I'm finding it weird that neither the front or back brake trigger it, I wonder if that narrows my search in case it's a wiring problem and not the connectors.

In the least this will give me an excuse to clean up some messy wiring.

I had a similar case with my OEM light that I switched back and forth to an integrated LED tail (Vizi-Tech:  SN490i and now an HSI SupaNova) and the main issue is how you have the lights hooked up.  Look at your Ducati wiring schematic and then connect to your CA tail.  Mine works now.  I have a '97 M900.

Thanks, do you recall what was the issue with your install?  I also had considered getting the Vizi-Tech unit.

Is the brake indicator light level stuck ON(Bright) or OFF(normal running mode)?

Sounds like the issue is upstream.  Could be in your brake levers. Most likely the front. But could also be the rear.
The little micro-switch they use are very fragile. If/when they break... they break in a "closed state". It's like brakes are always pressed.

To test:
1. With your bike electrical system ON.
2. Put a voltmeter(DC) on the stock "L" connectors between the BLACK(Ground) and RED(Brake Signal)
3. Check the voltage state. Should be ~0V with no braking applied. And ~12V when you apply your brakes.

run a test light to your factory harness. ground and switched...
see if the fault is between the tail and the switches...
hard to believe both the handlebar AND footswitches both failed...

thats what im thinking too.

The light level is stuck in a running state, not overly bright.

so NEITHER switch signal is making it to the tail....
test at both switches physical outputs first, make sure theyre functional, then move up and back from there....

Why both are not working?.... These switches are in parallel. If one is bad it will effect the other.

I see you have third party levers. CRG?
Make sure they are properly aligned on the little tab/switch so that when you press the lever it releases the switch all the way.

I'll try that, thanks

I was having a problem with the brake light being ON and then not working.  I do remember checking and re-checking my wiring and eventually solved the issue.  I referred back to the Ducati wiring schematic and the OEM tail - got that to work and then re-installed the Vizi-Tec. 

NoisyDante, did you ever resolve this situation?  I'm considering an integrated tail light unit, but your saga has me a bit put off...



Anyone else that went with an integrated unit - do you feel like you still have an acceptable level of visibility to other motorists, or do you wish you'd stayed with a larger turn signal set up?
///if this is a threadjack please feel free to PM replies, thx in advance for any opinions.

I actually haven't resolved the issue quite yet, but only because I've been so impossibly busy at work.  I was thinking I'd have a more informed mechanic take a look at the issue as well, it'll be in the shop soon anyway since I just got new forks to put on.

I think there is a wiring issue somewhere that is just cutting off the signal from the levers to the light.  I think it is mounted and wired correctly, and if there wasn't a break somewhere it'd work fine.

I think the visibility is fine, I don't think a larger light or spaced out turn signals are needed necessarily.  I'm always wary of people coming up behind me, but the light is brighter than most car lights, so I imagine it just is what it is.

I have the Vizi-Tec HSI SupaNova integrated tail/turn signal unit...and would not go back to the OEM setup.  The LED's are so much brighter than OEM...the turn signals are better, but can be seen better at night vs. day.  Allowed me to get rid of the ugly OEM setup. 

It happened to me. The rear brake switch must have shorted. I disconnected the connector by the brake lever and it started working with the front.

Issue resolved.

3 separate problems combined to make life confusing.  To being with, yes the leads were swapped.  In addition to that, the cylindrical piece that triggers the front brake was missing  [bang] .  Furthermore, the rear brake was not triggering due to damage to the mechanism in that the spike protruding form the brake line was bent, probably from the low side back in August and I never knew about it.

So there it is; cylinder, spike, and spades.  Light looks very nice now.   [drink]

Good news and a [thumbsup] for figuring it out.

Actually the [thumbsup] goes to senor Speeddog, he was kind enough to help me out with it after my suspension swap yesterday.  I NEVER would have figured this one out on my own. [bow_down]

I've got a rear brake switch if you need it. 

Aha... the Professionals  [bow_down]

Seems it was just a little bent but its working well now, thanks though

Indeed, though had those other two local issues on each lever not existed, then the leads would have been the sole culprit.  Good to know for future motodynamics purchasers.