heftymann Posted February 13, 2017 Share Posted February 13, 2017 So I am in the process of swapping out the OEM headlight for something custom. After doing some other custom work with handlebars and front forks the OEM front headlight stopped working. All I did was unplug it and throw it off to the side and when I plugged it back in it didn't work. I figured that maybe the bulb died but was upgrading to something else soon anyways. Now a few weeks later I have a different headlight and it doesn't work either so my first though was there must be something wrong with the plug? So using multi-meter, no voltage at headlight, no voltage at switch. There is power at the relay and headlight will work if splice wire from either red power in to the green connector (middle ground wire). Likewise voltage can be seen across multi-meter from both red wires and random frame ground. The yellow wire though flat-lines and there is no voltage across it. So relay doesn't seem to be the problem, but seems like it is not switching correctly maybe? Back at the fuse box, from power to ground across the fuse there is no voltage reading. But if splice power side of headlight fuse to another ground then voltage reading is present. Seems to be a ground issue? According to the wiring diagram the power goes from the fuse box to the relay then to the switch and finally to the headlight. But there is voltage present at relay even though no voltage present across fuse. Of course at relay there is no voltage across the main connector only the other ground. All fuses are good. Only thing that I am questing is no voltage across fuse when bike is turned on. But there is power at Relay which is weird since I thought it went through fuse first. Everything else works fine just no headlight. So it seems there may be a grounding issue somewhere between the headlight relay and the fuse box. I'm not really sure. I really don't know where to look next, any input is greatly appreciated. Thanks. Link to comment Share on other sites More sharing options...
mossrider Posted February 13, 2017 Share Posted February 13, 2017 Plug either headlight back in and start the bike, I bet they will both work with the engine running. ? Link to comment Share on other sites More sharing options...
Beemer Posted February 13, 2017 Share Posted February 13, 2017 Did you check the wires on your handlebars? You said it happened after the custom work. Beemer Link to comment Share on other sites More sharing options...
reboot Posted February 13, 2017 Share Posted February 13, 2017 Does your multi-meter have a tone out(probe) setting? If so try to trace the wires from the plug and see if you get a tone,if not you may have a broken or cut wire. That's where I would start. If they tone out then you can start to trace voltages. My gut is on a broken ground. Link to comment Share on other sites More sharing options...
rick Posted February 13, 2017 Share Posted February 13, 2017 Power to the relay might be thru the main fuse. The smaller individual headlight fuse might protect the switching side of the wiring. My Aprilia has relays controlling relays (sheesh, Italian electrics) and they are all powered on a 30A main fuse, but switched thru the secondaries.. Have you tried starting the motor? Dang, can't remeber (haven't started mine since mid-November dang-it) , but the Kaws I've had hands on won't turn on the headlight until some circuitry sees a charge voltage - up around 14-ish. That way the light stays off until after the starter is done. That "ground issue" might just be a diode that's shut off. Link to comment Share on other sites More sharing options...
heftymann Posted February 14, 2017 Author Share Posted February 14, 2017 Thanks for the replies everyone. It seems the issue was in the switch. When I took it apart it all kind of popped out. Everything looked good so I set everything back in place and put it back together. Seems that something was loose or just not set right cause now my headlight works. It did kind of get banged around a bit when I was installing the new handlebars so go figure. ..Wish I would have done that sooner. My biggest issue was the multi-meter readings that I took were when the bike was not running. ;-| So that is why the readings weren't making any sense because well it seems that the headlight on this bike doesn't turn on till after its running. But all is good now. Thanks. Link to comment Share on other sites More sharing options...
rick Posted February 14, 2017 Share Posted February 14, 2017 I was working on a friend's Ninja 250 that had a list of issues. When I was nearly done, I turned on the switch and no headlight - great! . My 1st reaction was that I'd screwed up something new in the process of fixing 10 other problems (had the fairing off) . Some Google searching led me to the circuitry that turned off the headlight until there was charge voltage. Fired it up, revved it a bit and the light came back on. Felt like a real dumbass after spending an hour looking at connectors. I've not ridden this Yamaha at night much and just couldn't remember if the light was on with just the key. Clearly not and that's why you had an open ground on that circuit with just the key on. My Aprilia needs every millivolt available to start when it's cold out. Of course, its lights are on as soon as the key is flipped, lol. So cool - good find. Link to comment Share on other sites More sharing options...
Beemer Posted February 14, 2017 Share Posted February 14, 2017 Knew it! Glad it's working for you now. Beemer Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.