Where to start?

[nastyjones]

I've been plagued with electrical issues this riding season. The latest one happened yesterday in downtown traffic. The bike just quit, and wouldn't respond to the starter button. Here's the strange part, all the other electrics work fine. I have headlight, turn signals, dash lights, etc. I tried shorting across the solenoid and the starter turned over the motor fine. Fuses look good too.

Any ideas where I should start looking?

[harley10]

I have had this happen to me and it was the the starter butten it self was dirty and a bit corroded , I cleaned it up and it was fine'.

[Ray916MN]

The bike quit while running and then wouldn't respond to the starter switch, but still cranks when jumping the starter solenoid? Sounds like the side stand safety switch to me.

[Steve]

The bike quit while running and then wouldn't respond to the starter switch, but still cranks when jumping the starter solenoid? Sounds like the side stand safety switch to me.

Just two things wrong with that statement:
1. Side stand switches did not appear until the '82 model bikes, his signature shows an '80.
2. Unlike many other bikes, that switch only turns on a light on the dash panel, it has NOTHING to do with whether you can use the electric starter, and it does not kill the ignition or anything else, it just turns on a light.

.

[wymple]

Run a hot wire to the coils. Bet it runs.

[posplayr]

DeOxit

http://www.thegsresources.com/_forum/showthread.php?237763-Recommended-Products-for-Preparing-Electrical-Connenctions&highlight=cleaner

[nastyjones]

Run a hot wire to the coils. Bet it runs.

You mean from the button to the coils?

I went through the bike last year and used contact cleaner then dielectric grease but will check again. Since I have lights and dash lights shouldn't I look at the ignition circuit?

[wymple]

No, straight from the battery. That bypasses everything and gives you a starting point. If it runs your ignition, coils are good.

[nastyjones]

I think I might be able to figure it out if someone shows me a schematic of the ignition system or at least explains it to me.
I need to know where to start.

[posplayr]

I think I might be able to figure it out if someone shows me a schematic of the ignition system or at least explains it to me.
I need to know where to start.

I can't tell if you have an ignition problem or a starter circuit problem.

The bike just quit, and wouldn't respond to the starter button.

These are two different issues but may be related.

If you can short the solenoid, and crank the engine then check the Green/Yellow wire to make sure you get 12V when you press the start button. If that is OK make sure the solenoid is grounded.

If your bike just quit, there are tests in the manual to check ignition. I assume you have not tested that. You look for spark if nothing else. Then Check the primary side of the Coil(-) to see if it is being modulated. If not check the ignitor ground.

[JTGS850GL]

http://members.dslextreme.com/users/bikecliff/images/GS1100wiringdia_.jpg

[Gorminrider]

wiring diagrams ...on the right! of this page..oh I see has been linked above..

http://members.dslextreme.com/users/bikecliff/

also gohere

http://members.dslextreme.com/users/storagecliff/images/electrical_odd-n-ends.html#A17

roughly speaking, you will follow orange/white wire from fusebox to Kill Switch..this turns your ignition ON supplying 12v+
thenif that's ok,follow orange/white to coils...then,given 12v is showing there, the white wire and the black/yellow wires from the coils go to the TCI (TransistorControlledIgnition) black box that controls when those wires go to ground, creating a pulse that makes a spark thru hitension plug wires...the TCI box gets its signal from the "signal generator"which is indeed a little generator with magnets that pass by coils to produce a little pulse of power that "opens" the Transistors in the TCI box....

Very similar to mechanical points,in case you still have those...it's the interruption of power to coils that creates a spark at the plugs
That's about it.
The starter button should have no consequence to ignition, but it's useful to note that the kill switch must be on for the starterbutton to work...it shares the orange/white wire.

[nastyjones]

wiring diagrams ...on the right! of this page..oh I see has been linked above..

http://members.dslextreme.com/users/bikecliff/

also gohere

http://members.dslextreme.com/users/storagecliff/images/electrical_odd-n-ends.html#A17

roughly speaking, you will follow orange/white wire from fusebox to Kill Switch..this turns your ignition ON supplying 12v+
thenif that's ok,follow orange/white to coils...then,given 12v is showing there, the white wire and the black/yellow wires from the coils go to the TCI (TransistorControlledIgnition) black box that controls when those wires go to ground, creating a pulse that makes a spark thru hitension plug wires...the TCI box gets its signal from the "signal generator"which is indeed a little generator with magnets that pass by coils to produce a little pulse of power that "opens" the Transistors in the TCI box....

Very similar to mechanical points,in case you still have those...it's the interruption of power to coils that creates a spark at the plugs
That's about it.
The starter button should have no consequence to ignition, but it's useful to note that the kill switch must be on for the starterbutton to work...it shares the orange/white wire.

A couple of quick questions. Where is the signal generator located on my gs1100? Also, I don't see a TCI box in the wiring diagram. Is it called something else?

[posplayr]

Ignitor....... It is connected to the coils

[JTGS850GL]

The "signal generator" is located under the right front engine cover with the TSCC emblem.