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jhubbz
10-21-2011, 09:43 PM
I think I'm about to throw everyone for a mind-trip, and will probably get chased after with pitch-forks for this, but here goes...

Is it possible to run H4 (hi/lo) bulbs in our cars?

(Doesn't necessarily have to be H4, but any hi/lo bulb)

I was looking at projectors and instead of having four of them, I was seeing if I could get them condensed into one housing and run the ho on a hi/lo bulb.

Here's my theory:

9005 has two pins, one for power and one for ground
http://www.r-spec.co.uk/bulbs/9005.jpg

9006 has two pins, one for power and one for ground
http://www.r-spec.co.uk/bulbs/9006.jpg

H4 has three pins, one for hi power, one for lo power, and one for ground
http://www.r-spec.co.uk/bulbs/h4.jpg



Given I have a harness that runs power straight from the battery so I don't melt factory wiring, and the necessary ballast for it, could I run the hi power to the hi pin, the lo power to the lo pin, and double up the ground on the ground pin?

Any faults in my thinking?

Please let me know because I am seriously considering this.

Also, I know it won't fit in place, but that's where the projector comes in, so I would be doing custom fitting anyway

tw0123
10-21-2011, 09:55 PM
you might be able to cheat a bit with this theory and snag a headlight wiring harness from a grand am... pretty sure they use the H4 bulbs and wiring might not be too complicated with similar cars...

cavaliers60
10-21-2011, 10:02 PM
I was wanting to do the same thing, but couldn't really figure out how to run both the high and low beams without losing power to the bulb itself.

jhubbz
10-22-2011, 12:08 AM
I was wanting to do the same thing, but couldn't really figure out how to run both the high and low beams without losing power to the bulb itself.

Maybe splice the low beam positive signal and run it to the hi beam positive signal pin?

So it would be:
Low beam (+) signal wire => low beam (+) pin
Spliced low beam (+) signal wire AND Hi beam (+) signal wire => Hi beam (+) pin
Low beam (-) signal wire AND Hi beam (-) signal wire => Ground pin

That sounds like it would work, but also sounds like it might blow up the bulb or something haha. That would probably work if you were running separate hi beam and low beam bulbs and simply wanted the low's on when they hi's are switched.

Shiwnath
10-22-2011, 01:13 AM
Well you could use a relay to keep power going to the low beam. Use the high beam signal to switch on/off the relay..i dont think there is an issue doing it that way...i could be wrong though...basically when you flick your high beams on, the low beam's factory power would cut off and the relay's power would then take its place.

robalero
10-22-2011, 06:43 AM
biggest thing here is how are you going to get that bulb to fit in the headlight itself. rembember each bulb has a unique way of fitting into the headlight itself that is your biggest feat to get over everything esle is simple with the wireing diagram of the alero.

jhubbz
10-22-2011, 07:21 AM
biggest thing here is how are you going to get that bulb to fit in the headlight itself. rembember each bulb has a unique way of fitting into the headlight itself that is your biggest feat to get over everything esle is simple with the wireing diagram of the alero.

ಠ_ಠ

Also, I know it won't fit in place, but that's where the projector comes in, so I would be doing custom fitting anyway

cavaliers60
10-22-2011, 10:10 AM
This might work for what you are wanting to do...

http://www.aleromod.com/forums/showthread.php?t=21715&highlight=low+beam

robalero
10-22-2011, 07:34 PM
yea j I never read that part my bad lol