Low Beam Out

I put in some IPF H4 Headlamps in last summer and yesterday while returning from 4 wheeling a friendly DPS officer pulled me over for having a headlight out( did not notice since I seemed to have more light showing with one than with people with two showing) Me and my rider was surprised and though I was let go with a warning I could not figure out why my high beam worked but low beam did not. I guess there are two elements in the bulb(IPF H4 Fatboys) Is there a way to repair the bulb? Is there a way to buy just one bulb? I will be going that direction again and will need to have it repaired before than.

you have h4 bulbs........

no you can't repair them, yes you can buy just 1 (even wal-mart carries them) It's not like the original headlights, all you have to replace is the bulb, not the whole reflector assembly that you got from IPF.

This is how bulbs work, thats why most of the time people drive with high beams on, so they have 2 working bulbs. There are two filaments in the bulb, one for low beams, one for high, same deal as a brake light. One filament is lit up for the low, and then when you need high, the other filament lighs up and puts out more wattage. No way of repairing the bulb, and I think you can buy single bulbs from IPF, but I would check their site.

Well, yes, there are 2 filaments on the bulb. No way I know of to repair the bulb, you'd need to be able to work glass and refill the envelope with the proper gas mix.

You can check the bulb with a DMM or continuity tester without knowing the pinout. If you see an open between any 2 contacts, you've got a bad bulb.

begster said:

This is how bulbs work, thats why most of the time people drive with high beams on, so they have 2 working bulbs. There are two filaments in the bulb, one for low beams, one for high, same deal as a brake light. One filament is lit up for the low, and then when you need high, the other filament lighs up and puts out more wattage. No way of repairing the bulb, and I think you can buy single bulbs from IPF, but I would check their site.

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just to be clear, the high and low do not light up at the same time on a factory H4 setup. This would cause the bulb and harness to overheat. Instead it uses the relative position of the element to the reflector to project light at a higher angle against the horizon.

My bad, I didn't think it sounded like that. But ya I know it doesn't light them up at the same time, I meant to say the high beam turns on, turning off the low beam. Cause ya, that would be a lot of power being drawn on the harness.

A friend told me this happened to him and said the low beam ground was not connecting so I pulled the headlight out and was pulling and pushing the plug and behold the light came on. He said it was common for the ground to come loose because of dirt and the bouncing around and if you have one low beam light out but have the other side high beam out you have a loose ground . Learned something new and thought I would spread the word. I am all for saving money.