| Author | Message | ||
     Crusty |
My wife's 2008 XB12Ss has started burning out headlights. They only last about ten minutes on the road before burning out. This includes both low and high beam. My first thought was that the voltage regulator had gone bad, and was overcharging; but a meter indicated that it was putting out 14.25 volts at 2,000 to 4,000 RPM. The '06 service manual says that anything under 15 V is acceptable. I then checked all the grounds that I could get to, and the resistance never exceeded .6 ohms from the headlight connector all the way back to the battery. I looked at grounding points, and all surfaces are clean and corrosion free. Nothing else is acting funny. The tail light is working fine, the speedo and dash lights are fine, the only problem is with the headlights. I'll probably tear into the wiring harness tonight when I get home from work; but I'm hoping somebody else has had a similar problem, and could point me in the right direction and save me a lot of frustration. | ||
| Spiderman |
Check the output at the headlights, but I am thinking if there is enough power to over amp the headlights you woulda seen burnt wires first. I am thinking either a bad batch of lights, assuming you are getting them from the same location. OR the mounts or headlight assembly is loose. Quick question, you are not touching the glass part of the bulb are you? | ||
| Ratbuell |
+1 on touching the glass. Oils in your fingers will literally boil on the envelope (glass), causing a blister and a hole. On stage lighting, you'd usually get a big ol' telltale wart on the glass if that was what killed it - looked like a lump of lava stuck to the side of a light bulb. Sometimes we'd have to break the bulb inside the light because it would swell up too much to be able to get it out! Other questions - are you getting the bulbs seated properly in the housing? Crooked can equate to too much vibration as much as a loose mount can. And, what brand bulb? Some brands out there do NOT like the vibe characteristics of a motorcycle, much less a big honkin' twin. | ||
| Crusty |
I've tried different brands of bulbs, and I'm being very careful to not touch the glass. However, I didn't check the voltage at the bulb sockets, so I'll try that before I tear into the harness. Terri hasn't noticed any unusual vibrations in the handlebar, but vibration may be the cause. I guess I could try a different brand of bulb. So far we've tried the stock Factory bulbs, Silver stars, Hellas and the cheap H7s from Advance Auto Parts. Maybe I'll try the cheap H7s from CAP auto parts if the voltage at the connector is O.K. | ||
| Malott442 |
Sounds like a connection or ground issue | ||
| Spiderman |
Check the headlight and mounts, for cracks and to see if they are loose. | ||
| Ratbuell |
Out of curiosity...what "started" the burning-out-bulbs habit? | ||
| Baldguy |
I had something like this happen to me a couple years ago. Both headlights went out within a mile of each other. At 6:30am. In the dark. Turned out to be a loose cable connection at the battery. Not sure why it didn't affect anything else. I didn't diagnose the problem til I'd ridden it the 10 miles home (once the sun came up). | ||
| Crusty |
O.K. I checked the voltage at the headlight plug it stayed between 14.25 and 14.30 at all rpm. No noticeable variation between low and high plugs. I checked the battery connections; they were tight, but I tightened them more. There were no cracks or breaks that I could see in the headlight housing or mounting brackets, and the bulbs were seated properly. I went to CAP Auto Parts and bought a GE H7 bulb. The filaments have a different shape from the Sylvanias, so maybe this will cure the problem. I'll know tomorrow, as we're going for a 100 mile ride. I'll report back tomorrow night. Hopefully with good news. | ||
| Crusty |
The GE bulb lasted 12 miles. Somebody suggested that it might be a bad regulator ground, so I pulled the regulator and scotch brighted the mounting points (both on the regulator, and on the frame)and sprayed the screws with WD-40. I took apart the connectors and inspected the pins and sockets. Everything looked good and had visible dielectric grease on it. I took apart the handlebar switch and sprayed WD-40 it it. I re-checked all the connections. If it's a regulator caused problem, why doesn't anything else act up? I've checked the voltage several times, and the highest it's been is 14.35. The manual states that it should be 14.4 - 14.6 V at 3600 RPM. I have a 194 bulb in the pilot light, and it's unaffected. Only the H-7 headlight bulbs. I'm starting to lean toward vibration being the culprit. Neither Terri nor I can feel anything out of sorts, but maybe it's some sort of harmonic that's causing it? (Message edited by Crusty on April 25, 2010) | ||
| Crusty |
P.S. I HATE electrical problems. | ||
| F_skinner |
Crusty, it sounds a lot like a short to me. Check the voltage (at the headlight) again and do the wiggle test. (turn the handle bar extreme left and right as well) That wiring harness is pretty tight around the neck of the frame. My guess is a wire rubbed through and is causing it. See if you can trace the three wires from the headlight socket back as far as you can go. My guess is you will find a wire that is exposed and is shorting to another wire or the frame. Frank | ||
| Mr_grumpy |
I'd guess an intermittent connection in the feed somewhere, causing a surge. One problem I've had with the XB is the relays, try swapping the starter relay into the headlamp slot. | ||
| Crusty |
I FOUND IT!!! There was a wire coming out of the main harness beside the coil that was sitting against the boot of the spark plug wire for the front cylinder. Even though neither wire was worn through, there was some wear on the plug wire boot. I rotated the boot on the coil for the time being, and re-routed the wire from the harness so it wasn't sitting on the plug wire. we went out for a 30 mile ride, and the bulb is still fine. This week, we'll replace the plug wires, and all should be good. | ||
| F_skinner |
 Glad you found it!!! | ||
| Sifo |
So a 12 volt bulb chokes on spark plug voltage. Makes sense. That's one I haven't heard of before. Congratulations on getting it figured out. I bet you feel a whole lot better now! | ||
| Crusty |
Thank you everybody for your suggestions. Chasing electrical problems is not the easiest thing for me. I appreciate all the help I get from this board. Buell riders are definitely a cut above.  | ||
| Xb9lover |
Crusty, congrats on your finding u should come help me find mine out lol. Well guys I have a little bit of a problem on my hands, when I turn my key on the little 194 bulb in the middle of my housing will click on but my headlight will not. Therefor I can't start my bike cause my fuel injection won't kick in and it is impossible to start. If I turn the key back and forth, I can get it to pop on and get it started. I've checked som. Wires and all looks good ground wise. I haven't gotten deep into the frame though and I did the wiggle test and the bulbs are fine. They're nit blowin out they just don't turn on. Is it ignition switch or a relay ya think. I haven't checked the relay yet. | ||
| Xb9lover |
Also does anybody know what that little 194 bulb in the middle of the two headlights is for anyways? | ||
| Limelight |
Parking Light for UK parking laws. I put a red LED 194 in the front and an LED in the brake and use the parking lock every time I park somewhere. Saved my bike the first day I did it with a woman doing a uturn into my parking spot. |
