i have a set of fog lights installed on my lt250 ozark quadrunner 2004 and at idle they are very bright, but the second i rev it, they dim out to about half intensity. i have checked the wiring and there are no shorts (fuse doesnt blow either) and its wired directly to the battery. what do you think could cause this? battery is charging at 15V pretty much constantly.

 

Check the grounds?

 

grounds are good. they only dim out when its revved up...when at idle they are super bright. they dont dim much but its enough to notice it.

 

pull the light out of the housing and lay it over the handle bars and try it.... i had that problem for a day... and was a bad ground right at the connector at the light, little corrosion. also check all the wires on the wiring harness under the gas tank and make sure no positive or ground wires are grounding where they shouldnt be, and are not loose. if that doesnt work, while you have the light out of the housing, get a multimeter tester out, read it while idle, then have someone rev it up and watch the tester as you read it .... tell results... does it go up or down when revved, or stay the same on the tester.

****edit just read op ... you have a diff light not oem light. so just put the tester on the connectors of the fog light, also are these fog lights ones you would put on a car or are they the smaller ones made for atvs/golfcarts off road stuffs? another idea would be to slap the oem light back on it and if it does the same thing then you know its the atv itself, if not then you know something is wrong with the fog lights.... maybe the fog lights are rated at diff ohms, volts ect.... im not sure im am by no means a electrician.... just an idea

 

im not sure if these fog lights were meant for something small or for the car, but they are about 4 inches wide by 1.5 inches tall by about 3 inches deep. i am running both stock and fog lights but the stock headlights dont seem to be affected as much than the fogs lights are.