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Discussion Starter · #1 ·
First mv is a 2013 F3 675 I love it but it keep breaking down on me. So the issue is when i turn my bike off and remove the key the headlight and display stays on and when i turn the bike on the headlight turns off, everything else runs normal. The display reads beam relay / can line. I have swapped out the relay and have the same issue and the fuses are all ok. Im not sure where power should be on a normal bike but i have power to the relay from the ecu at all times. When the key is out the handle bar control operates short of the horn the horn button for some reason will turn the display off when the key is out of the ignition. I really hope this isn't a ecu issue since the bike still runs fine.

I have the shop manuals but they don't show where power should be. at this point I'm thinking there is an issue with the ignition switch or the handle bar switch. I don't understand why with the key on i have power at the headlight relay all points (except the ground) and with the key off power at all points except the ground and the red/white wire that turns the horn on. If someone with a similar bike has time can see if this is a normal condition?
 

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Discussion Starter · #2 ·
So looking at the ignition switch 34 in the attached diagram. Please correct me if I'm wrong but I should. It have power when the key is off at red and green/ white. I have power with the key off and on positions. I'm hoping this is my problem and the switch is jumping power
 

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CAN line is the way the different computers talk to each other. So it looks like since you have already swapped the relay that the can wire is broken somewhere?

Thats my interpretation of the code on your screen. I could be wrong... but I think a call to MV should clarify what that really means.
 

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Discussion Starter · #4 ·
So for an update the ignition switch doesn't effect it at all even when disconnected. The black wire coming out of the headlight relay works properly as a ground with the key on. But when I switch the key off the ground at the relay is cut so there has to be a short to power for the light to remain on and the functioning handle bar switch. The ground up to the handle bar switch seem to function backwards. I'm not sure if this theory makes sense or how to test the switch to see if it is the cause.
 

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Discussion Starter · #5 ·
Thanks for the reply. I think I will have to call them. Since I can't isolate a short anywhere. And it doesn't make sense how the headlight light is on. With the key out the relay stays hot
 

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Are there any acceories installed like xenon headlight / led taillight / racing ecu / wiring etc.

If so i would focus on that.

I don't understand why with the key on i have power at the headlight relay all points (except the ground) and with the key off power at all points except the ground and the red/white wire that turns the horn on. If someone with a similar bike has time can see if this is a normal condition?
Under normal conditions if you turn on the ignition the 4 'leds' in the headlight and the rear tail light should illuminate. AFTER the engine has started the main headlight [h4] will turn on.
 

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Discussion Starter · #7 ·
I have a piggy back fuel tuner from rapid bike. The headlight leds work normal. When I start the bike the headlight doesn't turn on only when I remove the key.
 

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Discussion Starter · #9 ·
No, the tuner went in and i was riding for a wile, this has to be a new problem.. I swapped out the stock ECU and removed the tuner and the issue is still there. the only thing that fixes it currently is removing the headlight relay when the key is out that will turn off the display and headlight. Does anyone know what wire is the single for the headlight? it seems all wires are hot at all times except the red-white that turns on the brake light and horn.
 

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@mgucci: The is a MAIN RELAY and a GENERAL RELAY. parts 6 and 20 on the wiring diagram. I would check their function.
 

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Discussion Starter · #12 ·
Solved fyi for anyone else with similar issue. Under the battery the main harness was melting. Fortunately it was minor and I was able to repair it. I also suggest heat shielding the harness even if you currently don't have any problems.

Now I have to find out where my quick shifter went. I may have made a rookie mistake putting the harness back so I have to go check over my work but with the quick shifter on and even with the clutch in I can't go into second. Only when I turn it off I can shift.
 
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