Ive been having an issue with blowing low beam bulbs pretty often, and I got tired of it. I decided to pull apart the crappy sylvania sealed beam only to find that all it is is some crappy bulb siliconed into the housing, so I pulled the bulb out and hit some nice h4s in there.

I want to wire the whole system with some 12ga wire, but my question is where do I start wiring from? So far I hear just to splice right after the relay, but I want to go from the source. Ive heard to start from the headlight dimmer switch, anyone have any ideas?

 

I would start with the 5 pin weatherpack connector under the hood to each headlight. I would wire a relay (or one relay per side) from this connector, to the relay trigger, a 12 gauge wire/ (FUSED) from the lug on the fuseboxes. Run new ground from the radiator support, or from your grounding location
There is no reason to go before the relay, if the relay trigger still works. also no sense to have longer wires than necessary, so running back into the cabin, to the weak headlight switch is just silly.


This is how I wired my HID’s, I pulled the source of my relay trigger from the 5 pin weather pack connector, I remove the old terminal, and installed my own (I HATE cutting any factory wiring, so I decided to do this method) I installed a relay under the fuse boxes and a weatherproof fuse holder under the fuse boxes. I ran 14 gauge wire to both HID ballasts, but if you do not have HID’s just run the 14 gauge to your new headlamps

Ryan

 

Thanks for the info. Where is that 5-pin weatherpack connector located? Im not understanding exactly what youre saying. So pretty much I go from the 5pin connector to a new relay to the trigger relay? More info would be appreciated, thanks.

 

I think what hes saying is this. The factory setup uses a relay to turn the headlights on...DUh... from there he wants you to pull that weather pack apart and use the wire that normally feeds the headlights power and use it power another relay, so now you have 2 relays, which is ok.

its really just for simplicity's sake and that way its easy to run fresh power right from the battery to the headlight's.

Correct me if I'm wrong but thats what i think he was getting at.

EDIT: a quick scan of the schematic, i cant find a relay for the headlights. but the idea is the same, just make the normal power for the headlights a signal wire (with a relay), to pull power direct from the battery.

 

Ok I see what youre saying, thats exactly what I want. What kind of relay do I need?

 

I'll do my best to explain it. All relays have pins, which are named the same. 85 and 86 are your signal pins run your headlight power to one and ground to the other, this will make the relay work, you should hear it click. Then you can run battery constant to pin 30. once you have this run a wire from 87 to your headlight. leave 87a alone. it will work like this:

turn your headlights on,
power goes to 85 turns on the relay
connects 30 and 87,
then you have power to your headlight
the headlight turns on
the other pin on the headlight is ground of course.

 

Bosch-style relays used to have coils that worked in either direction but recent relays have internal diodes so you should now connect positive to pin 86 and ground to pin 85.

 

This is true, they use diodes or resistors to stop voltage spikes from back flowing into modules. good looking out.

 

Good to know!