Blowing the Signals fuse - GS1100G

[salty_monk]

So the first run out on the 1100G it blew the signals fuse. No big deal... new fuse try again. Was hoping it was just an old one. Same result... within about a mile. Interesting thing is that today I'm 99% sure I didn't use the signals as I didn't turn so I think that narrows it down a bit.

Anyone want to hazard a guess as to the culprit?

When it goes it takes out the rear light cluster, signals, brake lights as well as all of the idiot lights incl the gear indicator & neutral etc.

Guess it has to be one of those things or perhaps something in the bundle at the neck & it's happening when I make a turn... I couldn't replicate it in the garage yet.

Wiring diag:

http://gsarchive.bwringer.com/bikecliff/images/GS1100G_1982_wiring.jpg

GS1100G_1982_wiring by salty_monk, on Flickr

[Rich82GS750TZ]

i'd remove the tank and un-bundle the loom at the neck and look for a nicked/worn wire that's shorting when you turn the bars.

[posplayr]

Yes physical inspection seems first priority. This is where the SSPB would shine because it will detect the short and recover when it was removed; no blown fuses. This would likely make it much easier to find.

and no plans for a new run.

[salty_monk]

Yes, if I hadn't already sold it on I would have installed it on this bike... at the time I didn't know I would be getting it & also didn't know if I'd be keeping the 1000. I definitely see the benefits of it.

Could it be made more universal? More like the M Gadget? https://motogadget.com/shop/en/electrics.html

I think there is a market, that one is super expensive!


Having had this bike back to the frame & cleaned up this loom I am pretty sure that unless I've nicked something during install it's in pretty good shape from the outside in.

I think my first step is to sit in the garage making vroom vroom noises trying to replicate it. My thinking is that it is likely attached to the brake light or as you say turning the bars.. the only other thing is vibration. It's weird though that it doesn't blow right away if it was a short like that as I make a turn out of my driveway...

[Grimly]

Clip a test lamp across the fuse terminals and pull and prod things until it lights up.
You've found your short.

[posplayr]

Yes, if I hadn't already sold it on I would have installed it on this bike... at the time I didn't know I would be getting it & also didn't know if I'd be keeping the 1000. I definitely see the benefits of it.

Could it be made more universal? More like the M Gadget? https://motogadget.com/shop/en/electrics.html

I think there is a market, that one is super expensive!


Having had this bike back to the frame & cleaned up this loom I am pretty sure that unless I've nicked something during install it's in pretty good shape from the outside in.

I think my first step is to sit in the garage making vroom vroom noises trying to replicate it. My thinking is that it is likely attached to the brake light or as you say turning the bars.. the only other thing is vibration. It's weird though that it doesn't blow right away if it was a short like that as I make a turn out of my driveway...

Of course it could be made more universal but for me personally i wanted it to replace a stock GS fuse box in form and fit (and enhanced function). Something more universal would not.

[salty_monk]

Of course it could be made more universal but for me personally i wanted it to replace a stock GS fuse box in form and fit (and enhanced function). Something more universal would not.

Yep, I completely understand where your approach came from, just thinking that financially a broader approach might allow for a further run of units. We have some decent board producers that we are using now that are willing to produce in the 100 sort of MOQ

[salty_monk]

Clip a test lamp across the fuse terminals and pull and prod things until it lights up.
You've found your short.

Aha this is the sort of trick I came here for... Does it have to be a proper "test lamp"? The ones I've seen would be pretty hard to connect & still be able to pull & wiggle stuff. Ideally I guess I'd want to plug it in where the fuse came out.

[salty_monk]

Now it blows instantly, no riding needed so whatever it is, it got worse!.

I tested with a meter.. set to OHMs. The -ve to battery -ve & the live to the accessory side (left as you look at it) of the fuse. Instead of the "1" for open circuit I was expecting I got about 900 ohms. That figure varies wildly between about 1100 & 300 depending on what I do with the bars (i.e. turn left, turn right).

I guess it's in one of those two wire bundles that go alongside the headstock.

Looking at the loom I have repaired the wrap along the biggest bundle on the right side of the neck and that bundle definitely has the rear light, signals etc in it so I'm figuring that's where it is.... Now to open it up and take a look. What a PITA!

[Grimly]

Aha this is the sort of trick I came here for... Does it have to be a proper "test lamp"? The ones I've seen would be pretty hard to connect & still be able to pull & wiggle stuff. Ideally I guess I'd want to plug it in where the fuse came out.

I see you narrowed it down anyway, but for anyone else reading this, I just use a tail or sidelamp bulb either in a holder or with leads soldered to the terminals and the ends terminated in small insulated croc clips.
The bulb short indicator can be adapted to almost any type of fuse holder, using whatever connectors are necessary to plug in or connect with.

Those bundles of cables at the steering neck are notorious. Time and vibration take their toll.
After repairs I wrap the harness in spiral sleeving to give a bit of extra protection. Not had any more trouble since.

[Steve]

One place to look that I did not see mentioned: check the horn connections.

The horns are powered by the same fuse. One side of the horn has constant power, the other side runs to the handlebar switch, where it gets earthed (grounded). Since that one side is always hot, it could easily touch something if it came loose.

.

[bobgroger]

Mine did this exact thing. Turned out to be the hot terminal of one horn too close to the mounting bracket. On occasion it would ground out. Sometimes days between events.

[Big T]

If it's not the horn, check the back of the fuse box (you've been there before)

[posplayr]

Yes, if I hadn't already sold it on I would have installed it on this bike... at the time I didn't know I would be getting it & also didn't know if I'd be keeping the 1000. I definitely see the benefits of it.

Could it be made more universal? More like the M Gadget? https://motogadget.com/shop/en/electrics.html

I think there is a market, that one is super expensive!


Having had this bike back to the frame & cleaned up this loom I am pretty sure that unless I've nicked something during install it's in pretty good shape from the outside in.

I think my first step is to sit in the garage making vroom vroom noises trying to replicate it. My thinking is that it is likely attached to the brake light or as you say turning the bars.. the only other thing is vibration. It's weird though that it doesn't blow right away if it was a short like that as I make a turn out of my driveway...

I have several complementary designs already worked out, but it has laid dormant for the last 2-3 years.

[salty_monk]

I had a look at the horns, everything looks fine down there, the connectors have their rubber boots in place and the wires look decent. The horn can be a bit reluctant to get a full sound but I assumed that was a worn switch (however see note below).

I also removed the fuse box & broke it apart to see what it looked like inside. Totally different to the earlier glass fuse bikes. No soldering & no real way to get an internal short going on unless the "sandwich" of layers opened up which seems impossible when it's screwed to the plate.

One interesting thing.. as I had the meter to hand I had a go at measuring at the fuse block connector again on the ohm setting. Battery Disconnected (kill switch on/off didn't have any affect) I get a dead short to ground on both orange red (headlight which is working fine but interestingly shares the same ground as the reluctant horns) and on Orange green which is the signals wire with the blowing fuse... does that make any sense to anyone?

I connected a test light across the fuse terminals... just constantly on at this point & I can't get it to go off by wiggling bits of the loom.

I did re-solder the connection to the kickstand light switch on this bike but that seems to be fine and all of this stuff worked fine before the first ride. The only other thing I've messed with is the orange white for a relay mod.

At this point I'm resigned to opening up the loom, the big bundle where it comes out from the front of the fuel tank tunnel but I thought I'd post up my findings here first.