Topic: Aftermarket turn signals killed my tail light... Help!

[Beastman]

I'll keep this chronological and as brief as possible:

Everything original was working fine. (But I had to mess with it...)

Removed rear fender, tail light, rear turn signals.  Everything in the front still worked fine.

Replaced tail light with a turn signal housing, and used dual filament bulb from original tail light. Light worked fine. One filament when bike was on, bright (second filament) when brakes were pressed.

Replaced front turn signals with after market, didn't flash.  Grounded the white striped cable for each side and got the flashers working, but they no longer stayed on as running lights.

Replaced rear turn signals.  those grounded fine, and flashed fine.  Not sure if they were ever steady running lights.

Now my tail light does not act as a running light, but will glow bright when the brakes are pressed.  Trying to figure out what my next step should be...

[the technological J]

double check the bulb... then double check all your connections..... brown is the constant  so your low  filament should be connected to it.... is the bulb plug def a duel plug?.... and btw the rear lights are only flashers no running light

[Beastman]

The bulb looks fine, and was working perfectly before I installed the new turn signals.

ie: Before I put the flashers in, the tail light would glow constantly, and brighten up when I hit the brakes.

[Duke McDukiedook]

Is that turn signal three wire? It should be to be used as a tail light.

[Beastman]

The turn signal only had three wires.  But the third wire for the tail light is the ground, which I attached to the turn signal housing and it was working fine.

[Duke McDukiedook]

Year and model of bike?

[Beastman]

1978 cb550k

[Beastman]

Still not having any luck with this.  Any electrical experts?

[the technological J]

do u have a multi meter? i would follow the brown wire till you find around where it loses power.... if that doesnt work disconnect everything and start over

[marksman]

Possibly screwed up original connectors?  Why change the original tail light assy?

[Beastman]

Possibly screwed up original connectors?  Why change the original tail light assy?

Because I removed the fender.  The original assy is an eyesore.

I guess I will be troubleshooting this on my own tomorrow...

[Duke McDukiedook]

Pics will help us help you, sounds like you somehow managed to wire up a crapper.

[Beastman]

I'll take some pics.  Is it possible to loop a ground or something?  I'm not an electrician so I'm not sure. 

The original blinkers only had one wire coming out if I remember correctly, and the ground connects to the stalk where it meets the frame. 

The aftermarkets have two wires (red/black).  I connected the red wire to the stock wire, and spliced the ground wire onto the stock ground, then that grounded to the frame/stalk.

The strange thing is, if I disconnect the spliced new/old grounds from where they meet and head under the tank, the flashers still work fine.

[Beastman]

UPDATE: I am blowing my 7A (tail) fuse. Still not sure why though. Figured that might help someone here get an idea. I'm out of ideas.

[Toxic]

do u have a multi meter? i would follow the brown wire till you find around where it loses power.... if that doesn't work disconnect everything and start over

If you are blowing your tail fuse, do the above/ You have a short in the wire. Somewhere probably where you were modifying the wires to accept the new tail light.

Check the wire from the fuse panel all the way back to the tail. 

And if you don't have a multi-meter get one as your will find it useful.  Can't have one of these old bikes and not have one.

You don't need an expensive one.

[Beastman]

UPDATE: the tail light will come on with the key turned to "P". It's not the bright filament either. If I switch to "on" and press the brake, the significantly brighter filament will shine.

Note: I'm doing all of this with the blown fuse removed.

[Beastman]

Ok, rather than take a bunch of pics and try to make sense of them.  I took a short video on my phone and narrated it.  multimeter is next i suppose...

[marksman]

If the fuse is completely removed then you must have got your hot  (power )  from the wrong side of fuse block or wrong wire to begin with.

[marksman]

Beastman as far as new turn signals if you ground and then put power 1st to black wire and then power to black white what happens?  Interesting they have three wires,   like a redundant ground.?  or a dual purpose bulb (s) setup??

[Beastman]

If the fuse is completely removed then you must have got your hot  (power )  from the wrong side of fuse block or wrong wire to begin with.

I don't understand how I could be getting power from the wrong wires, if there's only a select few under the seat, of which I matched colors.

Beastman as far as new turn signals if you ground and then put power 1st to black wire and then power to black white what happens?  Interesting they have three wires,   like a redundant ground.?  or a dual purpose bulb (s) setup??

I haven't tried that yet.  The new turns only have two wires Black and B/W.  The green is the original ground from the bikes' wiring, which is why I spliced the b/w to the green.  They are single filament.

[marksman]

Beastman.    maybe as the brown wire travels  up to the front of the bike it is connected to  a wrong connector.  The key supplies power to the tail light,  also in the "P" position.,  but there is a brown with a blue stripe that comes from the 7 amp tailight fuse.   That brown with a blue stripe connects to a black wire I beleive up by the  headlight shell.

[Beastman]

Problem Solved:

Turns out I was sending power through the ground up at the front turn signals. The details will be mundane, but it ended up working after I eliminated the unnecessary connections at each turn signal. I now have a running tail light, and no fuses blown.

Thanks to all who contributed.