Are all H4 bulbs dual filament?

[k-mart]

ive always wondered that...

[timmy0tool]

yes sir they are unless you are referring to H4 HID capsules. all OEM type H4 halogen bulbs are dual-filament.

[k-mart]

yes sir they are unless you are referring to H4 HID capsules. all OEM type H4 halogen bulbs are dual-filament.

thanks tim! you even answered my second question, about the HID's.

i was just evaluating my options that would still allow me to use the DRL kit

[k-mart]

ok ok, i got another question....

say for instance you install JDM headlights and wire them the same as the USDM headlights. will both filaments in the H4 bulb be triggered?

[92vigor]

^^ no they wont. Something about the USDM wiring that doesnt do it. I have JDM headlights that use H4's and only one filament lights up and for high beam the H1 is triggered.

I dont know how to get both filaments to light up on the H4's... anyone?

[Kurobei]

DRL'z

^^ no they wont. Something about the USDM wiring that doesnt do it. I have JDM headlights that use H4's and only one filament lights up and for high beam the H1 is triggered.

I dont know how to get both filaments to light up on the H4's... anyone?

Checkout the DRL thread

You will need a daytime running light kit. This will let you run your JDM lamps to use h1's as driving lamps and your h4's as low/high beam. Although this method works...it still doesn't function the same as a Honda civics oem h4 wiring. The civics oem lighting turns off one filament automatically in the h4 bulb when you switch between high/low beam. I've heard that having both filaments running at the same time for long periods of time shortens the life expectancy of the bulb....

It would be nice to see if someone can figure out how to rig a civics lighting relays and harness to a cb7..that would solve the jdm lamp wiring all together and make use of the h4 bulbs dual filaments more efficiently and leave out the clutter of having a aftermarket DRL module inside our engine bay.

[92vigor]

well I do have the DRL module installed, the H1 bulb lights up when i turn the car on as a day light running light... if i switch to high beam then it turns fully on and if i turn the lights on, then it turns off and the H4 lights up.

what i wanted to do was when i switch to high beam, i want both filaments on the h4 bulb light up... because right now when i switch to high beams, the H1 bulb comes on and the h4 stays the same on low.

[rebels]

well I do have the DRL module installed, the H1 bulb lights up when i turn the car on as a day light running light... if i switch to high beam then it turns fully on and if i turn the lights on, then it turns off and the H4 lights up.

what i wanted to do was when i switch to high beam, i want both filaments on the h4 bulb light up... because right now when i switch to high beams, the H1 bulb comes on and the h4 stays the same on low.

you need to run the bright wire to a 3 prong connetor for the h4 bulb and run the bright wire to it, instead of going to the h1 bulb in the bright housing. then wire the h1 bulb to the running wire of the DRL kit.

thats how i was going to do it, but i never used my DRL kit.