(Solved)Need help wiring turn signals w/ Motogadget M unit

LeDom

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Hey there.. I'm in the process of making my wiring harness using a motogadget m unit and I'm having issues with the turn signal switch.
My problem is that regardless the way I connect my wires, and anyway I switch the turn signal switch, all 4 of the blinkers flashes. And it keeps on flashing until I toggle the switch again.

Looking at the stock wiring diagram, I see a ''flasher cancelling unit''.

http://cyclepsycho.com/yamachopper/wires/81XS650_wiring_(fixed).jpg

maybe thats the problem but a motogadget m unit is supposed to delete all the relays so my guess is either my switch is bad, or my wiring is wrong. Is there a wiring guru out here who can help me? Or maybe someone who built a xs650 using a M unit.


Thanks a lot
 
Do you have a link to view this motogadget m unit? Flasher cancelling unit was for shutting the signal lights off, I believe. I do know that if you wire any signal lights to a signal light indicator or winker in an aftermarket speedometer, there needs to be a diode in that line that goes to the indicator in the speedo, or all lights will flash like hazard lights. I went through that myself.
 
The M unit is actually really easy, it one wire to turn R, one wire to turn L, one wire to horn.. etc...
motogadget-m-unit-wiring-diagram.png


The part I dont understand is the 93 wires coming out of the stock control box on the handlebar.
 
Brown / white, power in from flasher relay.
dark green to right signal.
brown to left signal.
green to low beam of headlight
yellow to high beam of headlight
blue / black power in from right side headlight switch
Pink, horn

that's how they come out of my left hand switch, but that is a 1976 and 1978, not sure if that matters, I doubt it.
 
Ledom, best suggestion I have for ya is to scrape the forums for anyone who may have posted an MUnit and stock control setup. I seem to potentially recall finding 1 in here “somewhere” but it takes a lot of keyword swapping and reading.

I’m curious though, you’ve dropped the coin on an MUnit, why not go with the controls and mbutton as well? It slims the harness to almost nothing & makes the bars so much cleaner. If it’s a cost thing (and I get that) for the controls, just remember that you can also go with momentary switches out there but at 1/10th the price.

Hopefully someone here can clarify the stock control wires for ya. Best of luck man, the MUnit is a thing of beauty, love mine and will be in every build moving forwards
 
LeDom;

Your problem is due to the way the flasher indicating light is wired. Its 3.4 watt bulb is wired directly across the Dark Green and the
Dark Brown. That worked just fine as long as the regular 27 watt signal bulbs were the load. Things change when you wire the turn signal switch into the M unit. The M unit being solid state, means the turn signal switch is now sending current into a very high resistance device such as the base of a transistor, which takes very little current. The 3.4 watt bulb is relatively low resistance compared to the transistor, so it effectively ties the left and right sides together in parallel and all 4 lights flash.

You would need to disconnect the flasher indicating light, which could be as simple as removing the bulb. In order to recover the lost indicating light function, you could wire up 2 LED lights to be the indicators. One on the "OUT" terminal of the left and one on the "OUT" terminal of the right.

I know very little about the M unit. This is just my thinking about how it may work. I don't know if you have stock incandescent signal bulbs or LED signal lights, but it should not matter, as I suspect the M unit can supply high current or low current as needed.

Since the M unit controls the flashing, you would have to remove the stock flasher relay that is under the gas tank. Connect the brown and the brown/white wires together.
Remove the flasher cancelling unit as well.
 
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Ledom, best suggestion I have for ya is to scrape the forums for anyone who may have posted an MUnit and stock control setup. I seem to potentially recall finding 1 in here “somewhere” but it takes a lot of keyword swapping and reading.

I’m curious though, you’ve dropped the coin on an MUnit, why not go with the controls and mbutton as well? It slims the harness to almost nothing & makes the bars so much cleaner. If it’s a cost thing (and I get that) for the controls, just remember that you can also go with momentary switches out there but at 1/10th the price.

Hopefully someone here can clarify the stock control wires for ya. Best of luck man, the MUnit is a thing of beauty, love mine and will be in every build moving forwards

Actually the bike is not for me, the stock wiring was all messed up and i'm making a cafe racer with it so it had to be simple. I told the owner about the button and switches but she dont want to invest anymore so I gotta deal with what I have..

As for the search believe me it's pretty much all i'm doing of my time at the moment lol
thanks
 
There is no indicating bulb connected at the moment. I really think the problem is with the switch wiring. I'll go take some pictures
 
Oh nevermind, figured it out, turned out to be a shorted wire in the switch.
As for the fact that I had to toggle the switch two times to turn the signals off it was only a question of M unit configuration, this thing is so cool to work with.
Anyway thanks for the help guys
 
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