Headlight Brightness Fluctuates On Acceleration

J_C_3 · Post by **J_C_3** » Mon May 28, 2012 8:36 pm

So, I have an interesting question, which I hope turns out to be a simple problem with a loose wire.

Whenever I accelerate one of my headlights(and the "Brights" indicator light) brightness fluctuates, it dims, runs bright, dims, etc. At an idle it seems alright, but once I accelerate it's right back to it. I just recently replaced the voltage regulator with an R6 reg. about a month ago after a bad one killed a couple of my batteries.

I did a brief check on the wiring harness by the near the cluster/headlight/switch, but it was pretty brief and I didn't pull the tank cover off and trace down the wiring harness either.

Does anyone have any idea what this could be? Has anyone experienced this before?

Edit: Oh, and I have a 1989 FZR600, der. Sorry, about that.

Post by **DonTZ125** » Tue May 29, 2012 2:22 am

Sounds like something's loose and vibrating. Charging problems would be dim at low revs, brightening to some steady state as you rev up. Could be inside the switch itself, if the indicator is flickering.

J_C_3 · Post by **J_C_3** » Wed May 30, 2012 8:52 pm

So, I haven't had a chance to dig out the wires and check them out yet, but could it still be a loose wire if the headlight that was fluctuating exploded today?

The brights indicator doesn't fluctuate anymore, ever since the bulb exploded.

EDIT: Could it be because the back cap fell off on a ride the other day, and it rained that day? I recovered the cap, but haven't had a chance to get it on yet. Could this be a symptom of moisture getting in the housing?

haro504 · Post by **haro504** » Fri Jun 01, 2012 4:25 am

Check your voltage I'd say your voltage regulator might be bad as you rev it up the voltage will increase causing the lights to brighten. Just check for 14.5 at the battery. If it is bad you can do a lot of electrical damage so check it soon

J_C_3 · Post by **J_C_3** » Fri Jun 01, 2012 8:33 am

haro504 wrote:Check your voltage I'd say your voltage regulator might be bad as you rev it up the voltage will increase causing the lights to brighten. Just check for 14.5 at the battery. If it is bad you can do a lot of electrical damage so check it soon

I'm gonna check that tomorrow morning since I need to check my electrolyte levels anyways. But, would only a single headlight fluctuate with an increased voltage being output? Also, I did replace the regulator just a short time ago, and I did check the output after it was replaced. Now, that doesn't mean that it couldn't have gone out in that time...

cntryboy85 · Post by **cntryboy85** » Mon Aug 13, 2012 8:53 pm

the headlights on my 95 did the same thing and i couldnt figure it out. but i did kinda mod my lights to have both high and lows on at the same time and then put a relay to the wire for the brights so that they would burn brighter and it stopped the fluctuations.

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