Left signal won't blink, fan doesn't come on.

[Lawrence954]

I have a nice '75. The left turn signal comes on but won't blink although the right one blinks. Where should I start looking? The fan won't come on either. How would I test it?

 

[slabghost]

Signal that won't flash is either a bad ground, bad bulb (if one doesn't light),or the flasher unit. To see if the fan will work ground the wire from the fan switch on the motor with the key on. Fan switch simply completes the circuit to ground.

 

[cowboy45]

I've also noticed that with a bad battery turn signals fail. Make sure you have a good battery!

 

[Lawrence954]

Thanks, I'll start by investigating the ground for the left signal since I know the bulb/battery is good. I assume if the flasher was bad neither light would flash. The right one flashes.

 

[kerryb]

In my numerous forays into blinkerland, the solution has always been ground wire or low battery. While you have the blinker apart be sure to clean everything, including the inside of the socket.
Good luck!

 

[brianinpa]

Lawrence954 » Tue Jun 27, 2017 12:32 pm[/url]":13vkuv6j]
Thanks, I'll start by investigating the ground for the left signal since I know the bulb/battery is good. I assume if the flasher was bad neither light would flash. The right one flashes.

You would think, but I have seen where it only affects one side. Like others have stated... check the ground first then move on to the flasher.

 

[Lawrence954]

OK, so now where is the flasher located? While I'm asking, what setting should my tester be set on for testing the thermostatic switch for the fan. I've tested the fan and it works. I've watched the video.

 

[slabghost]

Flasher should be in the fake tank. AKA shelter left side. Set tester (multi meter) to ohms. Whatever setting works to read zero when the leads are held together.

 

[Lawrence954]

Well, since I started this thread I was able to get the signals to flash for a short time and I did get the fan going by replacing the non-functioning thermostatic switch. After that fix the signals quit blinking entirely. I don't think it was a coincidence but I can't think of what I might have disturbed while changing the thermostatic switch that would have affected the signals. There may be a clue here somewhere. The rear bulbs light but don't flash. It has a Vetter fairing and the bulbs in front are dual filament. The bright one lights on the left side but when I switch it to the right side both smaller filaments on each side dimly light. I pulled the lid off the flasher unit and the left light would blink and the signal buzzer sounded as I gently operated the flap inside the unit. The buzzer sounds continuously when I turn on either signal with the flasher unit out of the circuit which may be a warning that the flasher has quit.

 

[slabghost]

There is a ground not working.dim lights are feed back from power grounding through them.

 

[AApple]

+ 1 on the ground problem... :yes:

 

[Lawrence954]

OK, I get the ground not being solid (although I don't know where to begin looking for it) but why 2 filaments on a turn signal? I could understand it if one element was on on both lights during normal running and the other activated when the signal was applied. But I don't get why no lights, then one blinks on left, then 2 dim on right. Shouldn't just one element dimly light on the right rather then both if the ground were loose? The sockets look like new.

 

[slabghost]

It's possible a ground wire is hooked to a power wire on the load side which will power both filaments through the ground side of the bulb. Look for a green wire connected to another color. Verify it's right or wrong with the wiring diagram for your bike.

 

[mcgovern61]

If possible, can you get a picture of the wiring at the plug on the Vetter faring? The wiring there does not match Honda wiring color codes and the plugs have often been wired incorrectly.

Next, I would consider dropping the faring (4 bolts) and seeing how the harness is wired into the Honda harness. The original Vetter wire harness had the same bullet connector as Honda so it would be plug and play (if you will). But again, many people cut the wires and do their own thing.

 

[Lawrence954]

Thanks for the suggestions. Everything was working as it should for a few rides before I changed out that fan thermostatic switch so I'm pretty sure the wiring in the fairing is correct. I guess I must have disturbed something when I moved the radiator slightly forward to change that switch although I don't see how since I don't see any wiring near it. I guess I need to take a closer look.

 

[D-50Dave]

Those sound like the bulbs, 1157, used in older tractor-trailers. I would remove and clean every bulb and socket; they tended to corrode.

 

[Lawrence954]

Well, I got the lights to light up as they should (although I don't know what I did) but they still don't flash and since I don't know how to test it, I ordered a flasher unit. I did learn that the front lights are turn signal/position lights which explains the dual filament bulbs and sockets. I can't remember if the position lights, (what I would call running lights) ever did work.

 

[mcgovern61]

Lawrence954 » Thu Jul 20, 2017 11:49 am[/url]":ugded3pt]
Well, I got the lights to light up as they should (although I don't know what I did) but they still don't flash and since I don't know how to test it, I ordered a flasher unit. I did learn that the front lights are turn signal/position lights which explains the dual filament bulbs and sockets. I can't remember if the position lights, (what I would call running lights) ever did work.

On my Vetter faring and now my '82 Standard front turn signals (same bike), the position lights were on except when the turn signal was on. So, while flashing, the position light goes off as the other filament flashes.

 

[Ansimp]

+1 with the Vetter.