Turn signals inop. They have voltage to both sides?

[jon]

So I have been having a lighting problem with a 1980 GS450L . I have been attempting to change my turn signals over to led while at the same time up grading my reg/rec and stator do to the bike not charging.so at this point I'm not really sure if I ever had a problem or caused a problem or exactly what happened. At this point I have the charging system working correctly. But I still have a problem with the turn signals that I believe I have narrowed down to something I can't explain possibly do to a lack of understanding. With that said I currently do not have any of the lights plugged in. None. When I turn the key on I get battery voltage to the turn signal relay and threw it up to the turn signal control. Then when I move the turn signal control to either the left or right I get voltage to both the left and the right side. If I move the turn signal switch back to center or off,I then have no voltage to either side ,telling me the switch works fine. I have also taken it apart cleaned it and found no problem . Also I have taken the wiring loom apart looking for shorts and have found no problems. I have a new orange relay installed for use with led, and have check to see if it has the 2 wires on the same sides as it did when it was stock. I have also reinstalled the OEM relay as I don't have any lights hooked up , just to see if I got a different result. I didn't . It was the same. Can anyone tell me what I'm missing I would have thought the switch would have applied ground to the relay causing the relay to flash on one side or the other . It seems like such a simple problem but I can't figure out why I'm getting power to both sides when I switch it to either L or R and I don't know why I have power on both sides of the relay if there is no ground being sent from the switch . This is driving me crazy. Also I have noticed there are a set of white wires , one with a green stripe and one with a red strip coming from the same left side control. Seemingly going nowhere. I may have cut the old wire while replacing the rear fender brake and turn signal lights. I don't know. I started this last year. But I also read some where something about a switch that would turn off the head light for erouropean bikes or something. This bike has that and it is isolated so that the switch doesn't move. I don't think they need to be hooked up but just in case I figured I'd mention it. I'll try to upload a pic.

 

[pdqford]

Unless I missed it, might want to mention year/make/model.

 

[jon]

It's a 1980 gs450L

 

[pdqford]

"I can't figure out why I'm getting power to both sides when I switch it to either L or R and I don't know why I have power on both sides of the relay if there is no ground being sent from the switch "

I'll take a crack at this, but be assured, I might be off base f and cross eyed from trying to follow the wiring diagrams.

It appears to me that no ground is supplied by the "switch".
The ground is supplied by the socket of the appropriate turn signal lamps.

The switch only directs the current to either the left indicator lamps circuit or the right indicator lamps circuit.
AND to the turn signal indicator lamp (I don't think a burned out indicator will affect the turn signal function?)

Not sure exactly what specific issue you are having with the signals.

I believe you said ALL the lamps are disconnected.

So if those lamps are supposed to complete the grounds for the left/right signal,
there would be no current flow through the turn signal relay.
I'm not sure, but I think the current load through the relay is what allows it to interrupt the circuit


Hopefully someone will come along and explain just how the circuit is supposed to work.

 

[jon]

Everything you said sounds right to me but when I hook the turn signals up they don't work. Not does the indicator. And the bulb is good. I think the problem is somewhere in what you are saying but I'm still coming up short. I am gonna find some OEM lights and hook them back up to see what I get

 

[jon]

Ok. It's been a while since I started working on this so forgive me. Now that I have hook up both front lights I realize the flaw in your thinking that it is detecting the ground. It is I believe detecting the voltage when the turn signal switch is moved left or right and the problem I am having is when I move it right or left it sends voltage to both left and right at the same time. This causes both left and right to illuminate at the same time. Which is the problem.

 

[pdqford]

Ok. when the turn signal switch is moved left or right and the problem I am having is when I move it right or left it sends voltage to both left and right at the same time. This causes both left and right to illuminate at the same time. Which is the problem.

Ah,,so! I assume you mean that they don't flash when both sides are on.
The only commonality I see between the left and right turn signal lamps is the turn signal switch, the turn signal indicator light in the instrument cluster, and their grounds.

What I would try to narrow down on the problem is disconnect the indicator lamp from the circuit and see if that stops both left and right from lighting together.

Then I would disconnect the indicator switch from the circuit and verify its function with an ohm meter.

Any reason to suspect the wiring and the grounds are not unmolested?

 

[rphillips]

Thinking out loud, Does this bike have emergency flashers?, the only system that should be capable of sending current to all signals at the same time.

 

[jon]

I'm just now seeing these but you are spot on. I eventually did just that .I unplugged the harness going to the indicator lamp and the meter stopped beeping( by this time I have the lights all unplugged and I have a meter hooked up checking for continuity). So currently I'm assuming I have a short to ground maybe at the indicator lamp ,or maybe just added voltage to an existing circuit.i don't think a short nessasarily makes sense because it didn't blow a fuse or the bulb. But how ever. I noticed on my schematic it showed to turn signal indicators but my bike only has one. It seems as if there is a likely problem at this point where the two voltage wires come together,but it will have to wait until tomorrow. Buy this point I was done for the day . I will let you know what I find tomorrow.thanks.

 

[jon]

Ok so here is where I am at today. If I take the turn signal indicator bulb out and disconnect the the right rear voltage to the turn signal which is the light green wire the other 3 turn signals work fine .if I put the indicator bulb back in also leaving the right rear un hooked it makes all tree remaining turn signals flash at the same time. Also so you know my schematics show 2 turn signal indicator lamps but this bike only has one. The strange thing is that both left and right voltage wires go to this single indicator bulb the green one goes to the metal collar of the bulb socket and the black goes to the center of the bulbs socket. I'm not sure how this makes sense to have power pass threw the bulb on both sides . It seems as if the problem must be here but it's all OEM wiring and it appears to be in great condition. Well anyways see what you can do with that?

 

[jon]

Thinking out loud, Does this bike have emergency flashers?, the only system that should be capable of sending current to all signals at the same time.

To answer your question no ,it does not have emergency flashers

 

[rphillips]

shouldn't black always be the ground and should be connected to what you call the collar of the bulb socket. The power, or colored wire, should connect to the center 0f the bulb from the bottom of the socket... Just a thought and not sure if it could makes a difference. I've seen and used after market turn signals that seemed exact same as OEM. but wire colors were different.

 

[jon]

So,no the black is not the ground .it is left side turn signal voltage .black with white stripe is ground and for the bulb it is set up with power going to both sides. I believe the idea is when you active the turn signal switch it provides ground. You'll have to look at a schematic .

 

[jon]

I have changed out the rear turn signals with a nicer set and I now have managed to get all the signals working correctly right up until I put the indicator bulb in. Then all four flash like they are emergency blinkers. Any thoughts

 

[jon]

Another tibit of info. I noticed that In conjunction with all the turn signals working without the indicator bulb in, that when I do put it in that it will also blink with the 4 turn signal light that are all blinking.

 

[pdqford]

Ah,,so! I assume you mean that they don't flash when both sides are on.

What I would try to narrow down on the problem is disconnect the indicator lamp from the circuit and see if that stops both left and right from lighting together.

Then I would disconnect the indicator switch from the circuit and verify its function with an ohm meter.

Unless I missed it, have you removed the indicator switch from the circuit and verified its function with an ohm meter?

Even if it functions correctly, also verify that it can't cross feed to the opposite side.

Here's hopping we're digging near the potatoes

 

[rphillips]

Slightly mentioned earlier, those circuits should always be totally different circuits, not connected anywhere unless you have emergency flashers, which you don't.

 

[Cipher]

Check corroded sockets. Check pinched wires on the full path of the circuit.
Check for ground. Clean all bullet connecters and other connections in the circuit.
Carefully remove dismantle and clean all the bits int he shwitchgear. Dismantle in a pillow case so as to catch the flying bits that pop out suddenly.

 

[jon]

So I did everything you all had suggested with the exception of checking with an ohms meter. Kinda wish I would have saw this first. Anyways I got sick a not being able to figure out such a simple problem,I mean it's a turn signal circuit on an 81? So anyways I had been wanting to rewire the bike with some updated parts including a GPS speedometer and led turn signal that cancel . I had been waiting because this was one of 2 bike that weren't a project and that I could actually just ride. Well anyways I ripped out the old harness and rewired the whole thing front to back. It took a couple daze but we are up and running again. Thanks for all the help. I wish this would have come to a close with a happy ending that went something like .... I found it ! And this was the problem. But I got the bike going down the rode again so I happy either way. Thanks again.

 

[jon]

So I recently found a video that I believe would have had the solution.if I new how to attach the video here I would. Anyways it appears that I needed to connect a diode to the turn signal indicator connected threw the turn signals. There are a lot of videos on this subject I just had no idea. I've never had to do this before ,I simply installed the orange flasher relay you buy on Amazon and my new led lights have always worked. Anyways I figured I would come back and add this just in case someone in the future reads this looking for a solution.