Question about turn signal wiring

[a-aron087]

Working on double checking the wiring on my '82 GS1100GL and in the service manual it shows 3 wires going to the turn signals (Gray, Black, and Black/White) however my lamps only have two wires, Black and Black/White. I'm guessing the lamps aren't original but I can't find any original lamps that have 3 wires. Anyone know what that third wire was for? Any idea why I can't seem to find 3 wire lamps? The third gray wire is present on the harness side but there's nothing to connect it to.
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[Burque73]

If you have a test light, see how the circuit behaves when the key turns on, then when the signal is switched on. Maybe the grey is a constant power for running lights?

[bwringer]

Many models had three wire fronts using 1157 bulbs with two filaments; you had running lights using the dimmer filament and brighter signal lights.

My '83 GS850G's running lights; OEM signals:


In that wiring diagram, B/W is the ground, Gr is the running light wire, and Lg and B are the right and left signals, respectively. The signals themselves use the same three wire colors, but the B is hooked up to Lg on the right.

[a-aron087]

Many models had three wire fronts using 1157 bulbs with two filaments; you had running lights using the dimmer filament and brighter signal lights.

My '82 GS850G's running lights; OEM signals:


In that wiring diagram, B/W is the ground, Gr is the running light wire, and Lg and B are the right and left signals, respectively. The signals themselves use the same three wire colors, but the B is hooked up to Lg on the right.

Thanks! That's exactly what I needed to know. I had a feeling the extra wire was for running lights but couldn't find anything to corroborate that. I managed to determine that someone put the Model 'D' turn signals on at some point that don't have the running light feature, whereas my bike is a Model 'Z'. The turn signals had also been relocated to where the reflectors normally mount on the nameplate due to the previous owner having installed a Dyna Glide style fairing on the front.

[bwringer]

Sorry, just noticed that I made a typo: my bike is an '83, a "D" model (not an '82 "Z" model), and AFAIK, all the '83 Suzuki models had front turn signals with running lights. In fact, in that photo above, those signals are the black bodied signals from an '83 1100E; later on I acquired a set of the correct chrome bodied front signals with running lights.

However, I don't know how and when running lights showed up on other GS models. Judging from your wiring diagram, your '82 1100GL left the factory with running lights, but I have no idea whether all '82 models did, or what models and years did or didn't have running lights.

You sure can't tell by looking... 40 years is a long time, and a lot of these signals get damaged, removed, and/or replaced for other reasons.

[Alan Schlosser]

I had 2 1982 GS1100L models in the past and both had front running lights which is why you have 3 wires.

[unfocused]

Unless North Carolina requires front marker lights on your motorcycle, you don't need the grey (GR) wire.

Very few replacement units have a 3 wire set up although they can be found.

Be very leary of LED lights out of China as most of them don't like 14 volts and will blink funny. I have a couple of these if you're interested in them LOL...

If you want a set of 3-wire OE light fixtures I believe I have a set or two... In Florida, lights are an option, just like motorcycle insurance.

FTW - in Florida, if you wear a helmet you don't need insurance while riding in Florida. If you leave the state, they are watching for you in Georgia and Alabama.

[rphillips]

Not sure what your plans are, but K&S Technologies have aftermarket signals that, to me, are the same as OEM, other than the wires are different color from OEM...If your model came with running lights, their replacements will also have running lights. Been a while since I bought any, but usually on ebay appx. $30.00 ea.

[a-aron087]

Not sure what your plans are, but K&S Technologies have aftermarket signals that, to me, are the same as OEM, other than the wires are different color from OEM...If your model came with running lights, their replacements will also have running lights. Been a while since I bought any, but usually on ebay appx. $30.00 ea.

I've got to get a new set anyways so I'll probably go that route. Thanks for the recommendation!

[a-aron087]

Unless North Carolina requires front marker lights on your motorcycle, you don't need the grey (GR) wire.

Very few replacement units have a 3 wire set up although they can be found.

Be very leary of LED lights out of China as most of them don't like 14 volts and will blink funny. I have a couple of these if you're interested in them LOL...

If you want a set of 3-wire OE light fixtures I believe I have a set or two... In Florida, lights are an option, just like motorcycle insurance.

FTW - in Florida, if you wear a helmet you don't need insurance while riding in Florida. If you leave the state, they are watching for you in Georgia and Alabama.

I'd like to go as OEM as possible so the LED lights aren't a worry of mine. If you've got a set I'd be happy to buy them off you. I noticed that the parts diagram shows the signal grounding through a detached wire so I wonder if that's why finding 3 wire lights is difficult lol

[unfocused]

I'd like to go as OEM as possible so the LED lights aren't a worry of mine. If you've got a set I'd be happy to buy them off you. I noticed that the parts diagram shows the signal grounding through a detached wire so I wonder if that's why finding 3 wire lights is difficult lol

You are correct. Some were set up like this. I'll look at my set up and get back with you...

[rphillips]

If you use a signal with a dual element socket for running lights and it has 3 wires coming out of it, you won't need the remote ground wire shown in that diagram. The 3 rd wire coming from that signal is the ground and will plug into where the remote ground wire would have plugged to.