[SOLVED] Bike Won't Start 4/8/2020 (Main Fuse Blew)

I can hear your fuel pump running and the cranking seems OK (maybe a bit slow). If a jump got you up and running the first thing I'd do is get a new battery.

I bought a new battery at the shop. I was thinking new battery as well since the bike is about to go on 4 yrs. I brought in my old battery and they said it was good. I bought the new battery anyways. After blowing and replacing my main fuse (whoops...but thank you Yamaha for the circuit protection), the bike is back to it's old non-starting self. Why would the old battery test as good for all the tests they ran on it...but it's unable to start the bike. Also...with the new battery...there should be no reason for it not to fire up the engine ...but it's not. I agree...it feels like a new battery is needed, but the bike is not starting even with the new battery and likewise with the old battery ..which supposedly checked out to be good. She's still under warranty...guess I could have her towed in......I am thinking of getting a new bike....wonder how much she's worth...could another fuse be blown?  I was trying to get to the fuse box on the left faux air vent...not sure how to take it off after removing the two screws and the push pin...

Stop. How did you blow your main fuse??? Reversed polarity on the battery?  Main fuses don't blow without a good reason.  That's a whole different issue than just a bad battery.  

Did you put a good charge on the new battery?

Hey Hypernaked, I wouldn't worry about your battery. Sounds exactly like mine, and I just replaced the battery with an OEM... and fully charged it before installing it. I replaced it because also thought the battery was weak, but the new one only cranks a hair better, so that's just the way these bikes are. Having said that, the starter seems to pause a little bit, then keep cranking, in a kind of cycle. My bike hasn't cranked up that long yet, but glad to know the starter behaves that way.

Finally, your bike definitely has an issue, but the hard part is diagnosing it. The first thing to check is ALL fuses, and any DTCs. Do you own a code reader and adapter? If not, I'd start there. With these electronic machines, you have to. I had trouble with mine early on, but it turned out to be a tight EXUP cable, which I promptly fixed after getting the adapter and code reader. And yes, it's possible you might have damaged the ECU with the reverse polarity, or some other electronic component, but hopefully not. Good luck.

you check the basics? are spark plugs good? is fuel good? air filter good? could it be rectifier/regulator related?

FIXED!!!

So I got her starting again. It was NOT the battery, since I'm using the OLD battery and she fired right back up. I had blown the main fuse due to reverse polarity with a new battery. WHOOPS. I honestly don't know why she didn't fire up and I had to get her towed a week back...but I did kind of leave her in the rain a couple nights. But I've ridden her in heavy rain with no issues before, during or after. Anyhow I did not check the other fuses. WHOOPS. Replaced the main fuse. Everything lit up but the bike engine would only crank, but not fire up and hold idle. Finally removed the air scoop today to check the rest of the fuses. I would have done these earlier, but I worked 4 straight 12hour shifts...so that wasn't happening. Long story short, finally popped the airscoop off after trying to figure it out over the last couple days. There are "invisible" fasteners you have to remove, thus I'm attaching a how to. Low and behold, I found TWO other fuses had blown!! I replaced them with the spares. BIKE fired up!!! It did have an engine code about the throttle positioning not matching up but I took it for a test run and there's no difference in the throttle than when I rode it in the past. I had a fake out engine code in the past as well. Erased them and rode. No issues since! I'm attaching some photos that I hope help in removing the air scoop. Maybe I should have a separate thread...because no one shows it in good enough detail ...that I've seen ...not even the mechanics manual.

Thanks all,

Funny how more experienced people than I fell for the same thing.

It's lead me to another question, I changed the fuses and waiting to get the OBD2 scanner and it's connecting port!

However, I can't get in to the bikes menu screen. I have the MT10SP so I can't change any riding modes.

The bikes rides ok, sometimes I wonder much better than before she doesn't get as hot either, might be the weather change but hey it's better all the same.

did anyone have the same / similar issues ?

I have the heated grips and they seem to have stopped working too, might be there individual fuses but thought I would ask.