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Discussion Starter #1
Hi all,

The ST2 engine died a few weeks back just when I honked the horn and has refused to start since.

Mods: I posted this in the ST area a while back, but got no response that worked so I'd appreciate it if you could leave it in the general area where more might see this.

The issue: Lights, fuel pump, horn all work. Starter motor turns over but no spark at the plugs.

What I've checked: fuses (all good), swapped relays under seat, checked crank position sensor connection (seems fine/clean).

I've disconnected the horn to see if that made a difference, but no.

I can't help but feel I'm missing something simple as the engine died EXACTLY when I honked the horn so I'm sure there's a connection there somewhere. The horn(s) are dual FIAMMs with an inline relay and have never caused any issues in over a year.

Any hints appreciated.

Thanks,

Vinny.
 

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Old Wizard
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The stock horn pulls 60 watts so I assume each Fiamm does also. I have dual Fiamms and remember having to run the ground wires back to the battery to get a good connection. Trace your grounds to see what else is on the circuit.

I hope I'm wrong but it sounds like the computer saw a voltage spike from somewhere. See if you can borrow a computer to eliminate this issue.
 

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Discussion Starter #3
Hi Shazaam,

I installed a separate wiring harness specifically for the horns when I did the install. I think I got it from 'Eastern Beaver', a guy based in Tokyo.

I hope you're wrong about the computer too, but knowing your previous posts and expertise, I'd say there's a good chance you're right. Sadly, there is only one dealer in the country here and they haven't been good on returning calls when I tried to order parts before. I think I miss BCM.

Anyway, a friend of mine has a trailer, so worst case scenario, we'll take a spin to see the dealer in Dublin.

Thanks for responding.

V
 

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Do you have a side stand switch bypass? Those things are more temperamental than a menopausal woman.

If that isn't it, get a wiring diagram. (I will see if I can help on that one, let me call my buddy who has a shop manual.) If everything else is working, I doubt it is the computer but instead, something is grounding the plugs (coils) out and keeping them from firing. Many things on your bike will do this from the kill switch on the handlebar to the side stand switch and several others. I think your problem is most likely simple but given that it is electric in nature, tracing it down isn't easy.
 

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Discussion Starter #5
Hi 3-D,

No side-stand switch for me, although I've been mighty tempted to get one.

Thanks for the offer of finding a wiring diagram for me. Now that I have all the plastic off, I may as well double-check and clean all connections anyway, and I'll call the dealer re: computer issues.

Thanks again,

V
 

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How new/old is the battery? Is it fully charged? Have you tried some jumper cables attached to a car battery?

You could try disconnecting the headlight plug when trying to start it, as a method to conserve some energy. The starter will take everything a battery can offer, sometimes to the point where the ecu maybe under the low voltage limit.
 

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Discussion Starter #7
Hi Jack,

The battery is new and was fully charged when I took her out. I don't think that's the problem as the starter motor was turning happily - just no spark at the plugs. Thanks for the response, though.

V
 
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