75 400f electrical dummy

[sillyocis]

hey all. I have 95 percent completed my restore/ build and now I need to replace the ginormous tailight assemble that was stock on the bike. I have barely enough electrical knowledge to replace electrical parts. NOT enough to troubleshoot effectively although I have all the necessary tools to do so. My question is a two parter.
1. If i find a tailight that has three wires like the stock one....can I use it? I have ruled out all L.E.D. lighting so put that out of the equation. My concern is over dual filament and single filament bulbs. I know this is dumb but do all tailight/brakelights come with dual filament bulbs?


2. My turn signals worked but never flashed. they just light up. I have not checked the "flasher fuse" but have looked at it and there are wires on all the prongs. there are TWO. there is a third wire in the bunch (a green ground with a male end that looks like it would go on a prong nearby but there is no place for it to go. all prongs occupied. I cannot trace where the wire even comes from but it has a male end on it and since it is wrapped with the other two turn signal type wires I assume it is related. Is it possible the wriong type of flasher fuse is installed and it should have three prongs but only has two?. it has to be a ground as it is green. I don't need turn signals (illinois) but I would like the option for my own safety. Sorry, I am a huge electrical dummy and everything else is by the seat of my pants.

 

[Koestum]

I have a 75 400f.

On the taillight: Green is ground, green/yellow is from the brake switch, brown is the tail light. Green also connects to all the turn signals.

On the signal relay, I bought a three prong relay at Autozone but only use two wires: grey and black. I covered the other prong (the middle prong) up so it won't touch anything. (I burnt several fuses figuring out which prongs go to which wires)

Wires with stripes are usually used after a switch of some kind (on/off wires (activated by a switch somewhere)).

I'm using an LED brake/tail lignt. I'm using incandescent front turn signals and LED rear turn signals. If you have an incandescent bulb in line with the LED signals they will flash and you don't need a fancy/expensive thing to make your LEDs flash.

You can use a two filament bulb for brake/tail light or use separate single filament bulbs for each. A two filament bulb is like two bulbs in one (using a common ground)

 

[sillyocis]

two bulbs in one using a common ground. hence the three wires? Now that makes sense! now I can get a tail light and get back on the street. just didn't want to end up buying the wrong thing and wasting money as the budget is already blown. thank you. as far as the relay goes. I have the schematic and notice that there are three wires going to the relay. my flasher relay only has two prongs unlike the other schematic shows. I will google the part number and see if I can find a blow up part schematic with a picture of the flasher fuse and check for prong numbers. I am wondering if they just wont flash without the ground attached to something. thanks to all for the help. ZI appreciate it.

 

[Koestum]

I believe that attaching the ground to the flasher relay is how I made the headlight flash and blew fuses.... but go ahead and try it if you want

 

[sillyocis]

you know what....i pulled the stock signals out of the box and I have decided that until I can get these bastards flashing there is no point in buying replacements or even running with turn signals at all. (illinois)

 

[Koestum]

Here's the autozone flasher on my 400f. Gray and black only. I have incandescent signals on the front and led signals on the rear. If you have led on front AND back it won't flash.

 

[baby elephant guy]

you may need to run resistors to make the leds flash...

 

[Koestum]

you may need to run resistors to make the leds flash...

BUT it doesn't need to be expensive... if you put a normal bulb inline somewhere(for each side) it IS enough of a resistor to make the LEDs flash... you just might want to hide it somewhere (inside the headlight bucket is one possible place)