Signal Unit Confusion

[Tourmaster]

The 1981 GS1100E that I'm working on is actually a friend's of mine. This bike has many electrical issues that I'll be working through, but here's the first one I've run into.

First a bit of owner background comments. He mentioned that his signal lights would only work occassionally, so assumed he might just have a loose connection somewhere. When I got the bike to my shop, noticed that the signal lights weren't working at all.

Well ... as I was removing the battery and cleaning up some of the wiring connections, I noticed that the Signal Unit (not the signal flasher) white multi-connector and black wire single connector were both disconnected and just laying loose and unplugged in the battery box area. So I cleaned up the contacts and plugged these connectors back in. However, with a fully charged battery, the signal lights still don't work ... so I've got more diagnostics ahead of me for sure.



Anyways I have a few questions concerning the signal light system:

• How could his signal lights have been working if this "Signal Unit" was unplugged? I'm thinking this is impossible.
• What does this "Signal Unit" do, and is there any way of testing it? My older Honda's of this vintage do not have such a unit, and thus only have the flasher as part of the signal system.
• In the photo below of the Signal Unit connectors, I found an extra single green wire with a male plug end that was wrapped with a piece of electrical tape, which you can see towards the top of the white female multi-connector. What is this extra, dark green wire for? I can't see it in the on-line fiche diagrams.
• I'll be working through the entire signal light wiring connections, cleaning them up as I go, but would appreciate any diagnostic tips anyone may have to help me along. Thanks

[BassCliff]

Hi,

That bike has a Turn Signal Control Unit as well as a Turn Signal Relay (flasher). It is possible for the flasher to work without the control unit providing the flasher is the correct type and connected properly.

The TSCU handles the "auto-canceling" duties in the blinker circuit. It sends a signal to the TSR and tells it when to cancel the blinker (after a certain distance at a certain speed).

When my blinkers quit working, I bypassed the TSCU and installed an aftermarket flasher on my bike. It's documented on my website. The stock flasher and control unit are not cheap, but sometimes I am.

It could be that your control unit quit working and the PO disconnected it. Now it seems the flasher has quit too. You can either put it back to stock or install a cheap aftermarket flasher.


Thank you for your indulgence,

BassCliff

[Tourmaster]

Thanks Basscliff ... yep I also finally found the diagnostic chart for this sucker, but your explanation is nice and straight forward. While I was off-line, I went through all the connections and sockets for the entire signal system, including the handle bar switch. All contacts were cleaned and refreshed and now the entire system lights and instrument indicators are working and responding ... except that the lights still won't flash.

I can now hear the flasher buzzing away ... but it won't do its job. So many thanks and will certainly check out your aftermarket flasher modification article. Cheers.

Now I have another couple of questions:

• My rear signal light bulbs appear to be correct ( 12v/23watts). However, my front signal lights seem to glow very bright and one of them says GE 1154 .. and the other is oxidized and unreadable. An online search of this number indicates a 6 volt bulb? Anyways, what is the correct (aftermarket preferrably) signal bulb that I should get for this bike. I presume it needs to be dual filament for the running lights also.
• Also, the wiring diagrams I have lack the (gray wire I presume) wire indication for these running lights on the front. Am I missing something here, or just have a crappy wiring diagram?

Again, many thanks in advance for any help with this.

[Tourmaster]

Well, I think I just answered my first question and yes it appears that the previous owner installed the wrong bulb on the right front signal.

I installed the flasher from my Honda temporarily and the signal lights are all working fine, except the right side was flashing very fast. Took this bastard #1154 bulb out of the front signal and installed a #1157 and that side of the bike is just flashing fine now, also.

I'm still stumped on the running light issue on the front. The front lights are a dual filament set-up, and I believe the gray wires, which are all plugged into the main harness, are not working. I have checked three different wiring diagrams for this bike, and none of them show that running lights exist. Does anyone know if the OEM 1981 GS1100E, had running lights on the front signals? Why don't the wiring diagrams show this feature, if this is proper?

[BassCliff]

Hi,

The bulbs you want to use on the front are 12v, 23w/8w. You want the Stanley 1034 bulb and it can be had at Z1 Enterprises, or wherever you like to shop. I don't know what to say about your wiring diagram. There are wiring diagrams on my website that might help. I think the extra 12v wire in my headlight bucket is brown.


Thank you for your indulgence,

BassCliff

[Tourmaster]

Thanks Basscliff. And, based on your recommendation, I see the 1034 is a dual filament unit, which I can therefore assume means that there are supposed to be 8 watt front running lights on my bike, in addition to the 23 watt signals. Guess I now need to figure out why those suckers aren't working. At least I'm making headway. Cheers.