My scooter died

[vale]

A few days ago, I was coming back from work (downtow 300i ABS 2010). I took some potholes, nothing really big. At some point, after one (probably) 5 cm pothole, after 100m, all my lights turned off and the scooter stopped. I knew that I didn't perfectly secured the battery after a swap, and thought that a cable snapped. It wasn't the case, but the battery was extremely hot. I took it out. Next day, I put a newly recharged battery on it. The display started, but I didn't have time to try to start it -> again all gone. I checked the fuses, and 15A from Charge was blown. I replaced it. Again, all seemed to work well for 2 seconds, then again gone. The fuse was blown. I took the scooter to a mechanic. It checked the wires and none seemed to be broken. It checked the regulator and that one seems to be ok. His last though is that the ECU is broken and needs to be replaced.
Is there a way to check if the ECU is indeed the broken part? Could be anything else? It's a very expensive part, I don't mind to buy it but I'm not 100% sure that it is.
Thank you in advance!

[Ruffus]

ECUs fail pretty seldom.

Looks to me as if the regulator would have gone.

I would make sure by measuring at this three yellow cables from alternator whether there are at 3000 RPM 40 to 70 VAC coming out and if
YES
output regulator should be min 14.2 VDC towards battery.

More than 15 VDC means reg faulty and cooks up your E-system.

[vale]

But I cannot start it. With new fuse in place, it only lasts 1-2 seconds - not enough time to try to start the motor.

[Ruffus]

No other way to as to take an automatic fuse or multimeter with croc clippers and test all cables through.
There where it snaps, there is a short towards frame or another cable, etc.
Since your battery came off once I would start in this area.

AND btw: forget nowadays mechanics.

[vale]

AND btw: forget nowadays mechanics.

Yeah, the more I ask a few of them and hear the responses, I incline to not ask them again

Tomorrow I will bring it home and try to test it myself. I understand that when measuring stator cables, there should be no continuity and the value between them to be around 0.4. Is 0.4-0.43-0.41 acceptable, or they must be the same value?
Second: what are the values for a woking good regulator?
Third: if stator is broken but the regulator, not...should I replace them both, just to be safe?

[Stig / Major Tom]

Cyclepedia.com manual has a lot of good info for your scooter. Great working photos as well of the procedures and electrical info.
Stig

[Ruffus]

around 0.4. Is 0.4-0.43-0.41 acceptable, or they must be the same value?
Acceptable in this range.

Second: what are the values for a woking good regulator?
A rect/regulator (diodes inside) is not testable (on a non runner) with home appliances. Best and cheapest way is to buy an aftermarket piece for around €30,- , spliece it in and see the outcome.

But first check all connectors as said for shorts or ground touch/chafed off isolation, etc.

Before you get into your scoots bowels to change the stator do everything else to make it run.

-big connector between 3 yellow cables and reg rotten?
-connector out of reg (red/green) to battery rotten?
-groundcable from battery minus to engine rotten (saw several lately)?
-jumpstart from idling car
-sure you got fuel?
-sure you have a spark?
-sure your killswitch isn't on OFF?
-sidestand switch in order?
-all relays out and wiggled and back?

All this has to be assured before.

[vale]

Just a quick update for this topic: a issue was found with my alarm (which I never used). I will disconnect it for future. I will also remove the heated grips, just to have one less variable.
The bike is still not working but I have hope, and a new electrician on site, that all will be resolved

[Neil955i]

Good luck with it Vale and keep us posted?

[CROSSBOLT]

Will this help your new electrician? Not sure what nationality this diagram intended but it will assist you as it  has me many times.

[Ruffus]

Offtopic:
CROSSBOLT, good to read from again.

[CROSSBOLT]

Offtopic:
CROSSBOLT, good to read from again.

Just had to see what was happening!