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Discussion Starter · #1 ·
I've read a of of posts about malfunctioning turn signals and most replies say to check the ground wires. My symptoms are the front turn signal lights are lit while running, the rear lights are not. When I put on the turn signal, left or right, the front light goes out, but does not blink, the rear lights don't come on or blink. Does this sound like a typical ground wire problem? If not, any other ideas? The ground wires attach behind the coils and under the seat, correct?
 

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I would first check all the bulbs. The front signals use a dual filament bulb, one filament for the running lights that are always on (except when you activate the signals), and the other filament for the turn signals. I think it is a 1157 number. The rear normally uses a single filament bulb for the turn signals only. 1156 if I remember correctly.



Now just to confuse people, there are some bikes with sockets and wiring for dual filament bulbs on the rear. At one time you could get a red lens for the rear signals and it would also be used as a running light on the rear. One of my bikes had this wiring in place when I got it. I believe all states dictate that only red can be showing from the rear on a constant basis.



The bulbs can be checked by holding the bulb bottom contact (only one contact if you are checking a dual filament) against one battery terminal and using a jumper wire from the other terminal to the bulb's lower shell. Don't short the lower shell to the terminal while you are doing this. A direct short across the battery will quickly cause the jumper wire to get red hot.



If all the bulbs work, check the contact nubs on the bulb's bottom for arcing or flatting. Sometimes these contacts can become worn and not make good contact with the socket interior. Then use some Scotchbrite wadded up to brighten the socket's interior. Get all the surfaces clean and bright. Then put a dab of di-electric grease on the bulb and insert it correctly. A dual filament bulb will only fit one way.



Still no lightie? Check the ground inside the headlight shell. There should be a ground lug inside the shell that a green wire gets attached to. Check that all the colors match up on the wires from the signals to the wiring harness. Don't worry about the flasher being bad until you at least get a constant light from the signals. Flashers usually will allow the bulbs to light, but not flash when they go bad.



If you still don't have proper operation, you may have to start checking voltage with a meter or test light starting a the turn signal connections in the headlight shell. Then just work backward or forward from there until you find the bad connection or lack thereof. There isn't any way to do the checking until you are sure the bulbs are good tho. That would be like expecting the bike to run without gas in the tank. Do the bulbs first.
 

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Harbor Freight again has the good little digital meters on sale for $2.99 and it's a very worthwhile investment to have one and learn to use it. Great for checking continuity or stator resistances and that also means ground continuity from the socket. Of course it will check voltages as well, handy for seeing if your charging system is working up to snuff.
 

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Harbor Freight again has the good little digital meters on sale for $2.99 and it's a very worthwhile investment to have one and learn to use it. Great for checking continuity or stator resistances and that also means ground continuity from the socket. Of course it will check voltages as well, handy for seeing if your charging system is working up to snuff.


I just got one of those small multimeters for free at Harbor Freight yesterday. The had a coupon for a free one in AAA Home and Away magazine. They work OK. The leads are cheap and they are not auto ranging. But for general automotive use they are good.
 

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Discussion Starter · #5 ·
I would first check all the bulbs. The front signals use a dual filament bulb, one filament for the running lights that are always on (except when you activate the signals), and the other filament for the turn signals. I think it is a 1157 number. The rear normally uses a single filament bulb for the turn signals only. 1156 if I remember correctly.



Now just to confuse people, there are some bikes with sockets and wiring for dual filament bulbs on the rear. At one time you could get a red lens for the rear signals and it would also be used as a running light on the rear. One of my bikes had this wiring in place when I got it. I believe all states dictate that only red can be showing from the rear on a constant basis.



The bulbs can be checked by holding the bulb bottom contact (only one contact if you are checking a dual filament) against one battery terminal and using a jumper wire from the other terminal to the bulb's lower shell. Don't short the lower shell to the terminal while you are doing this. A direct short across the battery will quickly cause the jumper wire to get red hot.



If all the bulbs work, check the contact nubs on the bulb's bottom for arcing or flatting. Sometimes these contacts can become worn and not make good contact with the socket interior. Then use some Scotchbrite wadded up to brighten the socket's interior. Get all the surfaces clean and bright. Then put a dab of di-electric grease on the bulb and insert it correctly. A dual filament bulb will only fit one way.



Still no lightie? Check the ground inside the headlight shell. There should be a ground lug inside the shell that a green wire gets attached to. Check that all the colors match up on the wires from the signals to the wiring harness. Don't worry about the flasher being bad until you at least get a constant light from the signals. Flashers usually will allow the bulbs to light, but not flash when they go bad.



If you still don't have proper operation, you may have to start checking voltage with a meter or test light starting a the turn signal connections in the headlight shell. Then just work backward or forward from there until you find the bad connection or lack thereof. There isn't any way to do the checking until you are sure the bulbs are good tho. That would be like expecting the bike to run without gas in the tank. Do the bulbs first.
 

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Discussion Starter · #6 ·
Hi Blue. Thanks for the reply. The front running lights are on all the time, so I know those filaments are good. The rear lights are not on, but from your post, I assume the rear lights only come on as turn signals. When I try either turn signal, the corresponding front light goes off and stays off (i.e., doesn't blink). This happens with both left AND right turn signals, so I would suspect either the flasher or a ground. The only ground I checked was the one under the seat. I haven't found the one on the battery side. I will check the one in the headlight shell. From my symptoms, could it be the flasher (a lot easier part to access and replace)? FYI, I've had the bike since new and have 126K miles on it with only minor problems along the way.
 

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I just got one of those small multimeters for free at Harbor Freight yesterday. The had a coupon for a free one in AAA Home and Away magazine. They work OK. The leads are cheap and they are not auto ranging. But for general automotive use they are good.


Yea, sometimes they have them on sale for as low as $1.99, I must have 6 of them running around at work now for general purpose use. I keep my two Fluke meters locked up pretty tight.
 

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The front running lights and the turn signals use different filaments in the same bulb. So it is possible that just the signal filament is burnt out. Not likely tho that both sides burnt out at the same time. Were you doing any thing to the bike right before you noticed this problem?



When you activate the turn signal switch, the running light on that side should go out, and the other filament for the signal should then light up. It is very possible that the contacts in the thumb switch have gotten dirty and are no longer making contact. You might try opening up the clamshell and spraying electrical contact cleaner all around the switch and then operating the switch several times. Try to get the cleaner into where the contacts are. These switches are a little funkly to take apart and clean, so try cleaning without disassembly first.



If you still suspect the flasher, you should be able to short the two flasher wires together and the signal light will light. Of course, have the switch for the turn signals flipped to left or right first. The bulb will not flash, but stay on constantly doing this. The front running light will not go out when you are doing this, but the bulb will get brighter as the signal filament kicks in.



The ground in the headlight shell is just a tab, spot welded to the shell, that the wire plugs onto. If you have been inside there, it is easy to dislodge this and not notice it.
 

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Try the following...





Get a large lead of wire, stripped on both ends.





Turn the flasher on. Connect one end of the wire to ground. With the other end, touch it to various points, such as the front signal mounts. My rear flashers ground through the luggage rack, so if yours are the same, touch it to the luggage rack. If yours have separate ground wires, try opening the lens and touching to the bulb side.





That will let you know if you have grounding issues.



edit-



Most of the old flashers are bimetal type... They need specific load to flash. If the grounds are bad, it won't flash in the first place.
 

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Discussion Starter · #10 ·
The front running lights and the turn signals use different filaments in the same bulb. So it is possible that just the signal filament is burnt out. Not likely tho that both sides burnt out at the same time. Were you doing any thing to the bike right before you noticed this problem?



When you activate the turn signal switch, the running light on that side should go out, and the other filament for the signal should then light up. It is very possible that the contacts in the thumb switch have gotten dirty and are no longer making contact. You might try opening up the clamshell and spraying electrical contact cleaner all around the switch and then operating the switch several times. Try to get the cleaner into where the contacts are. These switches are a little funkly to take apart and clean, so try cleaning without disassembly first.



If you still suspect the flasher, you should be able to short the two flasher wires together and the signal light will light. Of course, have the switch for the turn signals flipped to left or right first. The bulb will not flash, but stay on constantly doing this. The front running light will not go out when you are doing this, but the bulb will get brighter as the signal filament kicks in.



The ground in the headlight shell is just a tab, spot welded to the shell, that the wire plugs onto. If you have been inside there, it is easy to dislodge this and not notice it.
 

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Discussion Starter · #11 ·
Thanks for the replies. I sprayed contact cleaner into the turn signal casing with no luck, but will take apart and visually check and clean contacts. I will also check ground inside headlight shell. I hadn't done anything to the bike since the last time I had ridden it (several days before the signals stopped working) and the bike is garaged. Will also check front bulbs filaments, but I doubt both sides would go at the same time. Will let you guys know how things go. Thanks again!
 

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Discussion Starter · #12 ·
Thanks for the replies. I sprayed contact cleaner into the turn signal casing with no luck, but will take apart and visually check and clean contacts. I will also check ground inside headlight shell. I hadn't done anything to the bike since the last time I had ridden it (several days before the signals stopped working) and the bike is garaged. Will also check front bulbs filaments, but I doubt both sides would go at the same time. Will let you guys know how things go. Thanks again!
 

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Discussion Starter · #13 ·
Here's where I stand... I checked all the bulbs and all filaments are fine. The ground wire under the seat is making good contact. I disassembled the turn signal switch and cleaned and sprayed with contact cleaner. I cleaned connections plugging into the turn signal switch. Finally, I tried a new flasher, still no flashing. Lights come on, but when each turn signal is turned on, the light goes out.



I was NOT able to find a ground wire inside and attached anywhere inside the headlight shell or the one that's supposed to be near the coil. Can anyone help me find these two ground wires? Anything else I can try? As always, thanks for the help.
 
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