1983 Suzuki GS1100ED --- "Big Boy"

And check power at both sides of the fuse. If you have 12v, run a test wire from the fuse to the back side of the connector, see if you can get all five bulbs to light up. Aka: brake, tail, license, and two blinkers. Just dont touch it to any black/white wires. There may be a small spark, like when you hook up jumper cables, don't be scared. If it's a big spark, smoke, or lots of heat, disconnect the wire. Just brush the wire on the plug, don't hold it. It only needs to be on long enough to varify lights are working.

Will do it tomorrow! All fuses are good.

And check power at both sides of the fuse. If you have 12v, run a test wire from the fuse to the back side of the connector, see if you can get all five bulbs to light up. Aka: brake, tail, license, and two blinkers. Just dont touch it to any black/white wires. There may be a small spark, like when you hook up jumper cables, don't be scared. If it's a big spark, smoke, or lots of heat, disconnect the wire. Just brush the wire on the plug, don't hold it. It only needs to be on long enough to varify lights are working.

Turn signals won't be 12v unless they're on. Retest the ones in the tail light plug while pressing on both brakes one at a time. You sure there's not a blown fuse?

Yeah, I did the brown and white wire with and without using the brakes. And I did turn the turn signals on using the left hand controls. The fuses appear to be good. Let me check with my multimeter. brb

Turn signals won't be 12v unless they're on. Retest the ones in the tail light plug while pressing on both brakes one at a time. You sure there's not a blown fuse?

P.S. Put the probe right on the negative battery terminal, that will rule out paint giving you a bad ground.

And varify those black wires with a white stripe are grounded well!

I'm going to take a guess on what to do. Poke the hot wires with the positive probe then stick the negative probe onto the negative terminal on the battery. Turn the ignition to ON and see if I get voltage. Should be 12V for them. BRB!

I did the above tests with the ignition switched to ON. I plugged my positive probe right at the block and bullet connector without unplugging anything.

Gray wire (license plate light) = 0.08v

White wire (I think it's the brake light) = 0.04v

Brown wire (I think this is the tail light) = 0.08v

Black wire (rear left turn signal switched on) = 0.09v

Light green wire (rear right turn signal switched on) = 0.09v

So these obviously aren't 12v. What is causing this? The bulbs are good. The fuses are good. So that leaves broken wires... For some reason, I doubt that ALL of these wires are broken but I will unwrap the tape on the harness tomorrow and see what I find.

I'm going to take a guess on what to do. Poke the hot wires with the positive probe then stick the negative probe onto the negative terminal on the battery. Turn the ignition to ON and see if I get voltage. Should be 12V for them. BRB!

Hey hey! It takes 10 minutes to remove the seat, tail piece, and take 2 pics.

The block connector on top and gray wire on top all power the tail/brake/license plate light. All of the others are for the rear turn signals. Then there is one spare ground wire for something....

Ah, I thought it was your headlight. Tests work for those too though, although they obviously don't have a high beam setting. How's the plug at the tail light look? Should be a 4 prong square plug IIRC.

I cannot remember..... I'll be back in a few minutes with pictures. Wait for me!

Ah, I thought it was your headlight. Tests work for those too though, although they obviously don't have a high beam setting. How's the plug at the tail light look? Should be a 4 prong square plug IIRC.

Check for ground and + at the headlight plug. Should be three prongs. One is ground, one is the headlight, one is the brights. Ground should be black, or black with a stripe. Put your multimeter on it's continuity setting, and jamb it in that hole, and the other probe on the negative battery terminal. Should beep. Switch to 12v, and leave the probe on the negative battery cable. Check the other two plugs. One should have 12v, one shouldn't. Switch on the brights, and they should either switch, or now the 2nd one will have 12v.

Report back your findings, this should be an easy fix, seriously.

Curly, my headlight works perfectly fine. The tail/brake/license light, turn signals, and gauge cluster are the parts that do not work.

Unless I'm missing something in your explanation?

Check for ground and + at the headlight plug. Should be three prongs. One is ground, one is the headlight, one is the brights. Ground should be black, or black with a stripe. Put your multimeter on it's continuity setting, and jamb it in that hole, and the other probe on the negative battery terminal. Should beep. Switch to 12v, and leave the probe on the negative battery cable. Check the other two plugs. One should have 12v, one shouldn't. Switch on the brights, and they should either switch, or now the 2nd one will have 12v.

Report back your findings, this should be an easy fix, seriously.

You can't temporarily run wires straight to a switched 12v source? I don't understand why the lights don't work, it's either a bad bulb, bad wire, or bad fuse. Multimeter will tell you in seconds which one it is.

Bulbs are good. Fuses are good. So it must be a bad wire? I think my wiring harness came off of an earlier model though...

1982 GS1100E right hand controls installed. It didn't work at first so I opened it up and cleaned the contacts. Now it works great!


Brand new throttle cable installed. The grip now returns perfectly.


Intake port of cylinder 1 looks good.



Now the clutch lever is VERY stiff. I think I over tightened the clutch springs a bit so I'll check that tomorrow.

You can't temporarily run wires straight to a switched 12v source? I don't understand why the lights don't work, it's either a bad bulb, bad wire, or bad fuse. Multimeter will tell you in seconds which one it is.

I ride to work every day.

Even when it rains.

Keep the bike.

I can't. The thing is none of the lights work so it is illegal. It will also take some time for me to fix it but I need a car before next week.

I ride to work every day.

Even when it rains.

Keep the bike.