30A fuse blown

[silverliner]

Hello Community,

I'm hit by an electrical problem and I have now clue what is.

What happened: After a 3 hour ride at speeds of 80-100 mph (I'm from Germany you must know), all of a sudden the 30A main fuse blew. I was on the left lane overtaking and suddenly all electrics except the HISS lamp went off. Just like somebody had the ignition switch turned to off while riding. Just managed to pull to the hard shoulder. Checked and found the 30A fuse next to the starter relay blown. Put the spare fuse in, let it run for 10 Minutes on idle with the hand on the relay/fuse to check the heat. All ok. Bolted everything back together, put my stuff on, 1st gear revving up und after a few meter the same happened again.

Finally I was recovered by the ADAC (AAA equivalent) and my bike was returned home a week later. Back home I checked the fuse, it was blown of course and put a new one in and since then the beast runs without any problem. So I checked all the wires for signs of shorts, all relais and connectors as far as I could reach them. Opened the switches to check for corrosion, nothing.
Without having a concrete finding, I changed the fuse/relais unit and the battery (it was a no name gel battery before, that although only 2 years old it seemed a bit tired) as a preventative measure. The first 200 mile trip was ok, but a bad feeling remains.

Does anybody have similar experience with such self-healing phenomenon?

Kind regards

Klaus

 

[ST Gui]

I'm guessing you have an exposed wire that has an intermittent connection to ground which blows the fuse. Operating the bike causes vibration which eventually causes the short and then it's lights out.

Have you tried looking under all the wiring looms where they pass over or along the frame? Electrical problems are seldom self-healing. They just go into hiding waiting for just the right time make your day. Miserable.

 

[playfair]

In order to blow the 30amp main fuse, the short must be located between it and the other fuses, else you would only blow one of the smaller ones.
I'd start by checking the heavy guage wire the 30 is on all the way to were it hits the fuse blocks. Probably chaffed it where it runs along the frame.

 

[st1300r]

Check this thread post one. It has an easier to read wiring schematic. Not a HISS version but should be very similar.
Does it pop a fuse when you move the handle bars lock to lock? Main fuse A at the solenoid (not fuse A in the fuse block) feeds the ignition switch.

 

[silverliner]

Thanks for you instant replies.
Well, I spent already a couple of hours with it. I took all the fairing off. Checked the red wire coming from the fuse up to the ignitions switch and all connected wires from the ignition switch down to the first fuse box. I checked all the wiring and connectors with no result. All wires running down the handle bars, the handle bar switches. Nothing. What I couldn't check are the wires that run between Tank and frame, but those are protected in massive plastic tubes. I can't believe there is a short to ground in this area.

Klaus

 

[Blrfl]

The ST is a centrally-grounded bike. There are ground wires in those bundles.

--Mark

 

[Outbackwack]

What year is the bike? I've heard of original fuses going bad just from age. Was the spare in the the fuse block as well? Other than that, I agree something has to be shorting. And that kind of short usually leaves a mark somewhere. Good luck.

 

[silverliner]

Hello Howard,
it's a MY2004 and yes, both fuses that failed were the originals, also the spare.

Thanks for the "centrally grounded" advice Mark. Don't like the idea but it seems I have to check every single wire, not only the power lines.

Thanks anyway.--Klaus

 

[silverliner]

Hello All,

just wanted to give a quick feedback. Have NOT found the root cause for my problem. Very annoying. Rechecked all the wirings, red one from 30A fuse to ignition lock,all connectors in between. red/black wire from ignition switch to fuse box. Found one bad self-made conncetion with poor insulation close to first fuse box, but no signs of short or arcing. Also the wire from ignition switch to RH handle bar switch, all looked fine. Openend the switch, nothing. As a preventative measure I did the following: Fixed the bad connection on the red/black wire, replaced the Relais/connector unit, where the fuse is loacted, replaced battery, as there was some no name gel battery installed that was - although only 2 year old - a bit tired. Did a 250km test ride with 100km Motorway at 100 mph, no problem so far. Will start another 400km test ride as soon as time allows around my place of residence just to simulate the situation where it happend. If it works, I will leave it as it is. But an uncomfortable feeling will remain.
Best regards--Klaus