Topic: 550 Turn Signals

[exponent]

At wits end I have no idea what's causing this but it's probably something dumb. 3 prong flasher connected, all lights connected all bulbs should be fine, all grounds connected and clean but when I hit the turn signal switch the headlight flashes. Rear lights flash faintly at high speed. I believe it's the front lights that are the problem

Video https://youtube.com/shorts/VJ-fZjgc1vI?feature=share

[bryanj]

If you have led bulbs its that if standard bulbs you bad grounds

[BenelliSEI]

Most flashers only need two wires connected. Show us a photo of what you have done?

[Alan F.]

Was reading through your previous posts to get some history on your adventure with this bike. Back in July 2019 you wrote:

The work order I have says that the main harness was replaced along with the battery, and reg/rec. The bike ran after that. The fuse box looks ok, no damage or corrosion.

And the day before you reported they'd rebuilt the wiring harness:

First Post! My 1978 is only running on two cylinders. 2 & 3 do not fire. I checked both coils and they are fine. The spark plugs are foul but the middle two are not worse than the other two. The wiring loom was rebuilt last year by ACME cycles in Chicago, they also replaced the reg/rec. When i tested the leads, both yellow and blue wires, I had no resistance. Not sure if related but the SP15A fuse is missing. Any help is appreciated, this is my first bike and (kinda) my first project and I would love to get on the road soon.

So my question is what exact wiring harness is in your bike? The wiring diagram for a 78 550 may not be entirely correct anymore.

[exponent]

Most flashers only need two wires connected. Show us a photo of what you have done?

The 550 uses 3: Grey to LH control, BLK from Key, GREEN to Ground.
Power to the switch is supplied on GREY. See attached, may not be exactly correct for your year, but the main harness should be very close. Can't speak to whether the replaced harness the shop installed/rebuilt is even correct anymore.

78 550, to the flasher is green black and white(?) All bulbs are standard except headlight which is led. No clue which harness the shop who rewired the bike used, might be the white wire going to the flasher. When it worked it was plugged in to the original two prong flasher.

[RAFster122s]

You will need to open the controls to see which color wire goes to the turn switch. If they have grey and black then you would need to find where they switched colors, if they did…
Continuity check between your white at relay and grey at switch will tell you if it is ok…

[Darren Jakal]

If it is a 78 then go to the Manual page on this website and check out the 78 owners manual PDF. There is a wiring diagram near the end (it is b&w but it works). From what I can tell this bikes only used 2 wires and the third is unused.

Cheers, dj

[exponent]

Most flashers only need two wires connected. Show us a photo of what you have done?

The 550 uses 3: Grey to LH control, BLK from Key, GREEN to Ground.
Power to the switch is supplied on GREY. See attached, may not be exactly correct for your year, but the main harness should be very close. Can't speak to whether the replaced harness the shop installed/rebuilt is even correct anymore.

If there is a WHITE at the flasher, then you or they have inadvertently connected that to the headlight LO feed. The “WHITE” at the flasher needs to run to the LH control to supply power. In truth, color never matters as long as the feed/flow/direction is correct. WHITE at the flasher sounds like it’s confused with the LO supply. Correct that, and you’re golden.
78 550, to the flasher is green black and white(?) All bulbs are standard except headlight which is led. No clue which harness the shop who rewired the bike used, might be the white wire going to the flasher. When it worked it was plugged in to the original two prong flasher.

I looked at it and the control and they're both gray gonna try resistance

[exponent]

Getting resistance from the controls to the flasher so I believe the problem is on the two front bulbs. There are only two wires coming out and on the diagram there are 3. There are no ground wires but there are grounds inside the light from the bulb to the bulb mount screw. Could these be it?

[RAFster122s]

If measuring the bulb resistance then yeah you will see resistance. Bulb holder grounds to fork ears through the turn stalk.
No, this is not your issue if you have ensured your bulbs are good...

[RAFster122s]

Have you looked at your headlight wiring since it is flashing?

[exponent]

Have you looked at your headlight wiring since it is flashing?

Yeah the signal wires are connected to same colors in the bucket I checked multiple times. Maybe it is the bulbs, they were new last season

[RAFster122s]

Which three colors are the headlamp connected to in the bucket.pull that wiring to ensure you are not getting a gray wire plugged into the white wire feed in the bucket.

[RAFster122s]

Your turn signals worked correctly last year?
Have you charged your battery?

[exponent]

Your turn signals worked correctly last year?
Have you charged your battery?

Headlight is green white and blue, battery is all charged always keep it on a tender

[exponent]

Ok I figured it out, when I tested it again I noticed that when I held the switch a little bit off fully on either side it would work. Looking inside it looks like when the switch was clicked completely to one side it wasnt connecting with one of the leads in the switch. Just barely enough to not completely connect the front two with the flasher. Could fix the switch but it was tough getting it back together. I'll just hold the switch at the point where they flash from now on :l