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Discussion Starter #1
Found headlight low bean going off after riding for 5 to 10 minutes.

fuse F3 was burnt so it was replaced but low bean still goes off

replaced the battery for a LFX one because could not start the bike in one cold morning, had to replace F3 once more, low bean still goes off

replaced relay B and just tested: low bean goes off after 5 min riding. Switching the engine off and starting it again, low bean comes back for another 5 min.

Any suggestion???
 

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Formerly - dagmvagusta
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You hit something on the head when you stated you had to replace again after the battery was replaced. I replaced my battery to with a shorai lfx and did not blow a fuse. Since you did it makes me wonder if there I a problem either with main wiring harness or the lines coming out if the battery terminal posts heading into your fuse switches. ( big fuses behind the battery). I had a similar problem with my tail lights. They only would come on when I hit the brake but not when the bike was running as they should. I had to end up tapping into another power source for the tail lights.


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Poor connection somewhere.....since the lamp comes on again once you cycle the key switch it could be vibration related??

I suggest checking all the connectors involved in the low beam circuit for a pin or socket not fully seated in the plastic connector housing. The starter circuit turns the headlamp off when the starter button is depressed to start the engine....that system is controlled by the ECM I believe. Hopefully that is NOT your problem.

Probably something simple, but difficult to diagnose over the internet. Good luck.
 

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I'd start simple and check the grounding...

btw only one bulb for both the high and low beam on this generation of bikes...

joe
 

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Discussion Starter #5
May be it is vibration related but I have found it takes a while to go off and is back on as soon as the engine is started. Loose connections are not so repeatable.

Could be the ballast overheating, but again, coming on soon after engine start rules this out.

I am considering the voltage regulator, normally unreliable in any bike. Is there any easy point to check its output??

The bad thing of headlight going off is daylight safety and compliance to traffic rules... Not considering the situation of coming back home after dusk.
 

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Ballast? Do you have HID lights? The cycling of the key indicates something is resetting...an electrical switch of some type. Since you replaced the relay with no change then you need to look at what controls that....

If you do have a ballast then that could be suspect as it will discharge and recharge when you cycle the key.

Do not think your regulator would be at fault. Doubt it could cause this symptom.
 

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Discussion Starter #7
MY 10+ have HIDs, at least those assembled in Brazil.

Troubleshooting than is not that easy.

So far unable to point if it is the lamp (closing to life end), ballast (not keeping arch voltage) or voltage regulator (dropping voltage after charging the battery)...
 
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