ongoing headlight issue

[kevxs]

So I've been fighting a wiring issue for a few seasons now.
The headlight / dashlights only sometimes work.

I've cleaned all my connectors last season and seemed to have fixed it but by the time it started getting dark early and I needed the light it stopped working again.

Fired the bike up the other day for the first time this year and still no lights.
I bypassed the relay so when they are working the lights come on when I turn the key.

I know what to do in theory, get out the multimeter and perform continuity checks of the wires from the battery to the headlight, however in reality I quickly get lost and am unable to trace the appropriate wires.

Any help with this is greatly appreciated. I've been getting so fed up with this I've almost been tempted to take it to a shop

HELP!

[GLoweVA]

While bypassing the relay will work, you need to make sure that the relay is what's at fault.
In other words, if (while the relay is bypassed) you lose your lights again, then you have a different problem and the bypass is just masking the real fault.
If this does happen again (with the bypass) check the fuse connection, it may be that you have a loose fuse holder.
If it doesn't happen again (with the bypass) then it's either your relay, or the wiring from the alternator to the relay (or the ground back from the relay)

[kevxs]

thanks, i'll check my fuse. I agree by passing the relay was not the ideal thing to do but like I said I'm getting desperate here, you can only clean connectors so many times before you get drastic. . .

[mikubuilder]

hey there, I don't have schematics at front of me, but a headlight system is pretty simple, you have three wires going to the socket, black, green, and I believe brown. I will be shooting in the dark, but from what I remember black is ground, brown low beam, green high beam. From your symptoms it sounds more like you're loosing ground somewhere, low/high wires come from left hand switch, you can check contacts in there as they often come apart...
To test, check green/brown for voltage, and black for continuity to the frame....and so on

double check with electrical diagram

[GLoweVA]

So I've been fighting a wiring issue for a few seasons now.
The headlight / dashlights only sometimes work.

I've cleaned all my connectors last season and seemed to have fixed it but by the time it started getting dark early and I needed the light it stopped working again.

Fired the bike up the other day for the first time this year and still no lights.
I bypassed the relay so when they are working the lights come on when I turn the key.

I know what to do in theory, get out the multimeter and perform continuity checks of the wires from the battery to the headlight, however in reality I quickly get lost and am unable to trace the appropriate wires.

Any help with this is greatly appreciated. I've been getting so fed up with this I've almost been tempted to take it to a shop

HELP!

If he's losing both the headlight and the dashlights, then the problem is 'upstream' of the headlight bucket. i.e. the relay. He bypasses the relay and the lights come on.

[mikubuilder]

Fired the bike up the other day for the first time this year and still no lights.
I bypassed the relay so when they are working the lights come on when I turn the key.



HELP!

so from this I thought they still don't work, even with bypassed relay....

[kevxs]

correct the dash and headlight does not work. but bypassing the relay did NOT fix the problem. my lights are still not working.

They worked intermittently before I bypassed the relay, they worked intermittently after I bypassed the relay.

They don't seem to come on or off while driving, but somedays they work, somedays nothing.

[Winterhawk]

Might check the left control on the handles bars. I think that I have some spare reserve lighting units and relay's.

The Yamaha shops will do nothing but charge a large amount of money for nothing. The younger guys at the shops have never seen an XS11 before or have a clue to it's problems. My current bike had work done by a certified Yamaha mechanic and stuff was so screwed up with the bike and carbs it took me 3 weeks to get it right. I've been Yamaha certified since 1981 and still learn everyday from people on here. LOL

[GLoweVA]

correct the dash and headlight does not work. but bypassing the relay did NOT fix the problem. my lights are still not working.

They worked intermittently before I bypassed the relay, they worked intermittently after I bypassed the relay.

They don't seem to come on or off while driving, but somedays they work, somedays nothing.

Okay, more intel!
Then it sounds like the relay isn't the problem.
On the 79SF, the power goes: battery, Main Fuse, main switch(KEY), Headlight fuse (Red/Yellow wire), Headlight relay, then to meter lights and Reserve Lighting unit, then to the dimmer (Hi/Lo) switch then to the headllight and high beam indicator.
So, bypassing the relay doesn't solve the problem, then your issue is most likely with the Red/Yellow wire at the fuse block.
The brown coming in from the key switch feeds all 3 brown wires to the fuse block. (headlights, ignition, horns/turn signals)

Maybe this might help a little. (ignore the headlight switch, it's for the '78 model)

[bikerphil]

Might check those round pins/recepticles in the left hand switch harness under the fuel tank, they tend to stretch out and make a poor or no connection. They can be tightened up by prying the recepticles closed with a small jeweler screwdriver.

[kevxs]

thanks guys! haven't had a chance to work on it yet but I'll let you know how it goes.

[BA80]

Had a similar issue with mine and tore the bike apart looking for the problem in JW's front yard. It ended up being a fuse that was not making good contact INSIDE THE GLASS TUBE on one end.

It does sound like fuse issue.

[kevxs]

i'm running the modern spade fuse block but I'll certainly be giving it a good check.

[TopCatGr58]

Also don't forget to take the left handlebar switch assembly APART, and inspect the wires and the contact plates...they have been known to come unsoldered there and can make intermittent contact! JAT.

T.C.

[kevxs]

Fixed!

thanks for all the help!

the problem was a bad connection at the fuse block.

seems the guy who installed the upgraded fuse block (me) did a bad job with one of the connectors. it must have been building up a lot of resistance cause the plastic was all melted.

trimmed the wire, attached it to a new connector and i'm good to go.

i should have found the problem a long time ago but that's why i'm not a mechanic and why this forum is the best!