5 wire headlight to the 3 wire XJ750 harness?

Hey all. I just bought a round headlight to replace the stock rectangle headlight on the 81 XJ750, but I have run into a bit of an issue. The headlight I bought has 5 wires coming out the back rather than 3. white = ground, brown = running light, green = high beam, blue = low beam, black = ground. I know I am supposed to connect the high beams to the XJ yellow wire and the low beam to the XJ green wire, and black to black...but when I do this, nothing comes on. Does the running brown wire need to run to the also connect to the green wire? I can get it to light up if I connect the brown wire from the headlight to the brown wire from the harness, but then the selector switch doesnt work in order to switch to high beams.

Thanks!

 

81 xj750 seca has a switch just for " runninglight" check your fuse and check the relay to make sure they are working. was the stock setup working?

a link to what you purchased would help.

headlight has a yellow/green wire a green/red wire and a black wire ground. when hi/lo switch is thrown you go from low to high with an outage as you switch.

the auxillery low beam has a red black wire and a black wire ground with its own switch on the control

brown wires are for directionals . what other mods have you done to the wiring ?

 

It's not letting me link the item, probably because it's on ebay.

There was some work done prior to my owning the bike. The atari was removed and a single an all-in-one speedo/ tack was added. The lights all worked as far as I know before I started messing with stuff. The new tail light I added works fine, as do the blinkers. The headlight is the only thing not working at the moment. The connector for the headlight had 6 wires going into it, with 3 of those going to the headlight itself (yellow/green, green/red, and black as you noted). Those wires went to green, yellow, and black on the connector. I believe 2 of the other 6 were brake/tail light related. I saw the wires for the auxiliary light and left those unplugged for now as I was under the impression they were not needed.

 

you need 5 posts first go to this link and make a few test posts
Test Zone


there is a link on removing the atari package you should check it out the solid color wires run to the atari then out to the color with stripes

 

this is the link you need to look at
Here's the wiring mods to remove the rectangular instruments
from the 6 posittion connector to the 3 position connector
yellow wire goes to Yellow/gGreen
greenwire goes to Green/Red

black goes to black
on the headlight connector

the brake lights need a jumper from green/yellow to to yellow/white wires on 6 position connector

tail lights need jumper on9 position connector L blue to blue/white wire.

on yamahas in the US low beam is the running always on light. so in your new headlight the low beam will be on unless switched to high beam

what is the running light is on your new headlight??

 

Thanks for the link. That's the page I was originally going off of which got my other lights to work.

There are actually only 3 wires to the main bulb I noticed today, and the extra 2 wires are to the "running light". So my guess is I have it wired correctly, and I must have screwed something up with the switch while reducing connectors. Will the headlight go on if the bike it not running? Even if I turn the starter over a few times?

 

headlight comes on after relay closes. relay is triggered from alternator spinning It will come on after trying to start it or when bike starts
headlight does not come on with key on only

only the 82 and 83 maxim headlight comes on with key because it does not have a relay and runs through the starter button when button is not pushed.
you can bypass the headlight relay with a jumper to test lights.

do you still have the glass fuses? check the headlight fuse.

pull relay check for voltage at the red/yellow wire that wire comes from the fuse. then use a jumper wire to the blue/black wire headlight should come on.

the L/B wire runs from relay to dimmer switch and auxillary switch to supply volts to them to be diverted to high or low beam and power the aux light when switched on

red/blue is power wire to aux light after the switch

this is how the headlight wires up shared ground 2 seperate hots

 

Did the jumper as you described and that worked, so I guess I have a bad relay. Thanks for the help!

 

or bad alternator output, bad diode block
ohm out the brushes and windings of alternator

you can test relay by putting 12 volts to the other connections

white wire and black wire you can use a battery charger if you have one

always test things before you buy things

 

Whew, this is much more complicated than I was expecting. I am used to wiring stuff and not having to worry about diodes and relays. Turns out, the relay works doing what you described. I will test the other parts once I look around online as to how to do that haha.

 

way down the bottom of this thread is your tests and specs
The Ultimate Relay, Switch, Sensor, and Diodes Guide