Yamaha MT07 Signal Lights Fuse keeps blowing

[Hebis]

Hello Guys,

Glad to be here, first post  

So i have the problem mentioned in title. My lights fuse (L/R signal and hazard lights) keeps blowing after some time (Sometimes immediatly  after i change it).

I could not found a schema with the circuit from the fuse box to the parts where is connected, maybe that would help me troubleshooting this problem. (i don't know what exactly where is the problem, trying to identify)

Sometimes its even worse, its working only the left signal, but the right signal not. Also the hazard lights not working. (maybe that will be helpfull in a way, that a signal still works,when the other not)

Any tips/ideea where should i look for an open circuit ? How can i troubleshoot this ? I have a multimeter ready for use

All i found was this scheme with the switches.

Best regards,

Adrian

[sweetscience]

Insufficient data..

What type of bulbs are they?  What year is the bike?  Are you running aftermarket turn signal relay?

 

[Hebis]

Hey @sweetscience, sorry for that

Model is MT07 2017

Bulbs : H4 halogen bulb for the main headlight and i think T10 incandescent bulbs for the turn signals (didn't replace them, so i think those are used by default)

No, not running an aftermarket turn signal relay.

 

[ElGonzales]

My most likely theory at the moment:  the problem is a short circuit to ground between the turn signal switch and the right side turn signal lights OR the dashboard OR the hazard switch. It's the green wire coming out of the turn signal switch.
This would make the left side turn signals work, but blows the "parking light" fuse as soon as the right side turn signals or the hazard switch are used. This is your problem as I understood until now.

How to check?

-Remove the bulb of both right turn signals.
-Disconnect the dashboard. Just to be sure because of it's green turn signal LEDs which are also connected in parallel to the bulbs
-(Quick-check your multimeter. Because you never know... we want to measure electrical resistance or use it's continuity check. Hold the tips of the two test probes together, the display should show a very low resistance close to 0 Ohm. Take them away from each other, the multimeter should show an infinite hight resistance. )
-switch everything off. Main switch off, no turn signal activated, no hazard switch activated.
-measure the resistance between  the right turn signals inner and outer light bulb contact. Front/rear doesn't matter for now. Try to move the handlebar left/right and look at the multimeter while doing this. Move parts of the wiring harness you can reach.

The resistance should be veeery high (no continuity), never close to 0 Ohms because the positive contact is not connected to the engine ground, the turn signal relay is open.

You have continuity? This means, the green wire that connects the turn signal switch, front/rear right side bulbs, dashboard LED and hazard switch has an isolation fault somewhere, a contact to ground (metal frame, negative wire...) what causes a high current that blows the fuse.
Problem is, they are all connected together by a star-point (position actually unknown to me) what makes it hard to locate the faulty spot.

You can compare it to the left side turn signals, but you will also have to remove both bulbs on this side.

I am writing this from the couch right now in the middle of the night, sorry I can't provide pictures or own measurements for now. 
Send me a private message with you E-Mail and I send you a wiring drawing extract if this helps you.


 

[sweetscience]

I would check the turn signal/hazard relay, and the in/output voltage.  This relay is located at the left side of the bike, behind the R/R.  It will be the smaller one of the two, closer to the front of the bike, iirc.

The indicators and hazard are both integrated in this relay.  Since they are both wonky, I would suspect a broken relay.

Sec. 8-135..8-138 in the service manual.  Wiring colour for input is Blue/red stripe.  Output is Brown/white stripe.