Calling electrical Gurus.

[Cal Price]

My old '81 Yammy continues to confound me.

Until very recently the turn signal worked fine, despite vandalism and a couple of replacement items. (after being pushed over last month) When I signal right, they flash OK but the dash indicator light does nothing. Signal left and the dash indicator shows a constant light but the signals do nothing. Briefly the dash indicator worked for turning right but not now,

Any ideas John Bates, Srinath ??

[starwalt]

Hmmm.

I'd have to see a schematic. Got one or a reference for an online one?

Srinath? He's afraid of electricity. 

[Cal Price]

Hmmmm I bought the bike last year after it rested for eight years in a garage, I dont think a wiring diagram would help as this beast seems to have been rewired by someone who had their own ideas. To be fair they have used colour coding but i don't thik it bears much resemblance to the schematic in my Haynes manual. It some point id I keep it I may have to consider stripping out all the wiring and starting again.

[LimaXray]

I would go take a look at the wiring and try to draw up a schematic of the turn signal wiring.  If all the wiring is color coded it shouldn't be too hard to trace all the connections.  You may figure out the problem by just looking it over when you make your schematic, but if not you could always scan/photograph/draw in Paint your schematic so we can take a look at it.

While you're at it, check all the wire harnesses involved and make sure none of them are damaged/corroded/disconnected. 

[hmmmnz]

trace the wire back from the signal indicator on the dash back to the relay, there is a dodgy point in there some where. id say at the indicator end. probably a bad earth, so check there first and resoldier the point if needed
have fun

[Cal Price]

Yeah, my instinct was the switch but I will trace the wires, check the joints and earths. Thanks.

[John Bates]

Here's a shot in the dark.  Looks the same as ours.  From yamaha-triples.org

[joedude]

That is very similar... Interesting how the front L&R and aft L&R have common grounds. Simplicity is Key, and they got it!

[Cal Price]

Well I finally had an hour or two yesterday afternoon so I thought I would check out the wiring. I traced the wires back to the bullet joints and checked for current with my multimeter, there was current in roughly the right places at roughly the right times which is as much as I have learned to expect from this bike, so before starting to check all the earths/ground connections I thought "simple things first" removed the covers on the signals to find that the two left side bulbs were blown.

Some prat, who probably looks remarkably like me and shares my initials, had put six volt bulbs in, I did not know I had any but what the heck. I found a couple of 12v bulbs, a 10w and a 15w instead of the recomended 18w and put them in just to see what would happen, what happened was a perfect fix. This took about 15 mins so I spent the rest of the allotted two hours tear-arsing around the coutry lanes, must remember to pick up a couple or three 18w TWELVE volt bulbs ! ! !

[NiceGuysFinishLast]

Hah.. too bad I didn't see this sooner, I'd have told ya that's what your problem was.... Oh well, all's well that ends well! Glad you got everything right again!