No headlight/fog light all of a sudden

Hi guys, It's been a long time since I posted. Mostly due to not riding the bike much. Anyway, this morning I decided to ride to work. Bike started fine, everything worked great. When I came home and drove into the shed I noticed that I didn't have headlight. Nothing on high or low, and no fog light either. I shut it off and restarted, still no head/fog lights. Turn and tail/brake work fine. The Atari didn't indicate any problems either, so I'm guessing it's whatever sensor keeps the headlight off until after you start it.
Not sure where to start looking, but if anyone has a suggestion I'd appreciate it.
I didn't have time to look at fuses or anything tonight, have to do that in the morning.
Thanks!

 

Start with the fuses then the bulbs... I'd then look at the switch followed by the ignition.

Last time I had a headlight outage it was a broken wire on the back of the ignition.

 

The wierd thing is the Atari didn't set off the alarm light for the headlight. Not that I trust it completely, but it does work for the side stand, tail light and battery alarms. That's why I'm wondering if it's whatever circuit/sensor keeps the light off until after starting. Not even sure if it's RPM related or voltage related, but I think it's RPM.

Still, fuses and bulbs will be checked.

 

Does your wire diagram show a "headlight relay" anywhere. Not sure but I think the Seca has one where the Maxim didn't that year.
Rick would know for sure.

MN

 

I didn't notice replaced fuse block in your list of completions. Make sure you check that out real good as it is a known problem for these bikes.

A quick check of the wiring diagrams Here shows that there is indeed a relay for the head light curcuit.

The parts diagram shows it to be along the backbone under the tank. Look for the connector with the following four wires
Red/white stripe
White/blue stripe
Black
Blue/black stripe

There is also a diode block in the curcuit, and I believe that is located in the spaghetti bowl that holds the headlight.

Ghost

 

Thanks guys, haven't had a chance to look at it yet. Maybe this afternoon. MiGhost, I know the fuse block is suspect on these. But I haven't replaced it...yet. So far I've not had any corrosion or resistance built up in mine. The bike has always been inside when not riding though, so maybe that helps. I looked it over again a month or so ago and tested with DVOM, the ohms where at 0. Still that'll be checked again.

 

Finally got a chance to look at it. MiGhost FTW. The little holder for the headlight fuse was a little loose. Pulled the fuse, went to tweak the little tangs back together and one busted off in my hand. So, next project for the bike: New fuse block! I figured it was coming sometime, so no worries. I have most of what I'll need already, just need a little time to get it done.

 

It's a pretty easy swap... $100 question, was that the cause of the problem?

 

The fuse was still good, but the little clips that hold it in place.....weren't. One side had loosened up just enough so it lost contact. When I tried to gently push it back together one of the ears just broke off.
So, relay/diodes/wiring was fine, just and open in the circuit at the fusebox. When I hold the fuse in place by hand it works fine, but that'd be hard to do while riding.

Anyway, I'll have to find my good soldering iron and I expect I can stretch the project into at least an afternoon. I could use a little therapy.

 

I had a similar problem for a while, and it just baffled me for a long time (this was before I discovered XJBikes.com).
No headlights. So I followed the whole troubleshooting sequence: Bulb, fuse, relay, wiring, diodes, etc... you name it, I checked it.
The relay was working, I tested it on the bench, but wasn't getting energized when the engine started.
Finally, I discovered that, although the alternator was still working (somewhat charging the battery), it wasn't providing enough voltage to trigger the relay circuit. I discovered that because if was I reving the engine at pretty high rpm, the headlight was suddenly coming on.
Replaced the stator and it's been working fine since.
There's probably a bunch of you that would have known that, but I can see how some people would be as baffled as I was.

Guy

 

Sometimes they do that without you even touching them. They crystallize over time, and will break all on their own.

Radio Shack sells "panel mount fuse holders" that employ nearly identically-shaped fuse clips; they can be used to rebuild a stock fusebox.

The recommended fix is of course to upgrade to a modern, blade-type fuse panel.

 

skills, I just replaced my fuse box on my xj650j which I got from Chacal. I would highly recommend it, all of my lights got "brighter" afterwards. Obviously the corrosion on the stock fusebox clips was causing some resistance. check out my recent post search "sweet Cigarette" for my post it has pics of the new box.

 

Finally got my roundtoit yesterday! I did a temporary fix and only replaced the connectors for the headlight circuit fuses. I'm still undecided if I want to convert completely to blade fuses or keep the stock look. The radio shack 4 circuit block just donated a few parts for now. Rather than using the slide on connector for each end I just soldered the wires directly to the fuse terminals. Otherwise it wasn't going to fit in the OE box.

The more I think about it, the better I like the idea of switching to the mini blade fuses. So far though I haven't had much luck finding a block that will for sure fit under the seat.

 

XJ4Ever (Len) has one that will fit.

 

My 81 XJ650 did the same thing. Would start when it wanted then not. I just bypassed the relay & now the light fires when I turn on the key. Motor fires up no problems.