1979 GS850G auto-cancelling turn signal modul

[ldolamore]

I posted a while ago about my right turn signal working every time, but the left turn signal does not always function. The left signal worked 99% of the time in cold weather but not in warm. I replaced bulbs but no improvement. I doubt the flasher relay is to blame since it has only two wires and operates 100% of the time when right signal is engaged.

When either signal is operating, it never auto-cancels, no matter how far I drive after stopping/turning. I have to manually press down on the turn signal switch to turn off. I've been informed that my bike does have auto-cancel, and I considered looking into bypassing the module, but where is the module and what does it look like? I thought it might be inside the headlight assembly but nothing obvious to me. Or maybe the previous owner has monkeyed with the system, although everything I've checked so far seems original.

I suppose it's possible that the turn signal switch has a problem with the left turn contacts but I've been avoiding disassembly of the left handlebar turn/lights/horn assembly because I don't know what it contains and I'm concerned that springs and pieces will fly everywhere. I know to cover it with a bag but worried I'll never figure out how to reassemble.

[Steve]

Yes, your bike has auto-cancel signals. Unfortunately, it's the old style. I know there was a thread quite some time ago that dealt with how to bypass it, but I don't know where it is.

Your older system works quite differently than the one on my '80 850, and I have no experience with it, but I <think> the control unit and flasher are on the right side of the battery box.

.

[ldolamore]

Thanks, Steve. The turn signal flasher relay is under the left side cover but I didn't see anything nearby that could be the turn signal module. I also looked inside the headlight assembly and the speed/tach assembly, but I'll look around the battery. I searched the internet for a photo so I know what I'm looking for but so far haven't found one.
Since the right signal functions 100% of the time I feel the problem with the left signal should have a simple solution, but then again I know very little about the "magic box" module so maybe just wishful thinking.

[Steve]

On my '80, the flasher and the TSCU (Turn Signal Control Unit) are next to each other on the right side of the battery box. As mentioned, the systems are completely different and not interchangable.

I think the work-around for your system involved removing the control unit and installing separate flasher units for each side, then cancelling them manually. Not an ideal solution, but at least it's reliable and consistent.

.

[Nessism]

Fig 12-37 in the factory service manual shows the location of the TSCU.

[Guest]

sorry guys but i need to bring this thread back to life. my 79 850G is having turn signal issues. The right side works perfectly fine but the left side is a no go. the lights dont even turn on. I have checked everything and it all points to the module. I sprayed some contact cleaner on the board and it worked for a short period of time but it is now not working again. How does one bypass the module and just have regular turn signals? I heard something about wiring a second relay in the circuit so you have one relay for the right side and one for the left side. Any and all help will be appreciated.

[ldolamore]

sorry guys but i need to bring this thread back to life. my 79 850G is having turn signal issues.....

Man, I'd love if someone could provide a detailed explanation of how to bypass the turn signal module. I've had this issue for years. Like you, right side works always, left side not often. I've been trying intermittently over two years to figure this out. The left side almost always works in colder weather ... but not every day. A few times I've cleaned wire connectors for the module, and wires around the flasher relay, to find the left side then functions. But the next day it's dead again and the bike hadn't even moved overnight.

[Sander]

Hi all,

i have a 850G from 79 with a nom functioning control unit and having problems to replace with the original part here in The Netherlands. Love to see the workaround if available!

regards from Across the pond
Sander

[Nessism]

https://www.thegsresources.com/_forum/showthread.php?207726-79-1000S-self-cancelling-bypass-mod

[Sander]

Thanks!!!

regards,
Sander