Confused: JDM Headlight Wiring - Honda Prelude Forum

E_Luder · 04-01-2004, 07:48 AM

These questions are a little premature but I would like to get all my ducks in a row before tackling the wiring of my JDM lights. Now reading this has me a little worried. From reading the installation in the 4th gen FAQ I was under the impression that you could cut the USDM harness off and solder the H4's in without a harness. Is this correct?

quote from FAQ
.... If you would like to use the USDM 9006 and 9005 light bulbs: Cut the USDM harness off from the 9006 and 9005 lights. DO NOT CUT the side signal lights! They are reusable with the JDM headlights.

Now the Nokya harness sounds like a good idea but here are my questions. Will the H4's run without issue on these harnesses? How does having this harness stop the wires from melting?
The more I write the more confused I get. Someone please straighten me out.

Thanks

E_Luder · 04-01-2004, 08:01 AM

k.... The more I read the more I think I am starting to get it. In the thread here I think the missunderstanding. When he mentioned harness I thought of the wiring itself but I think that the actual connection harness was being referred to. If so I would need something like this to properly interface the H4 bulbs with the stock wiring I have. Am I on the right track?
As well I mentioned this before but I'll ask again.... Can I solder the wires right onto the lights? I won't do this but I am curious. I would assume no due to the finish on the terminals of the bulb.

Please let me know if this makes sense.

Thanks

Si_g · 04-01-2004, 08:35 AM

i wouldnt solder the wires directly to the bulbs. It might work, but i m sure you are not using stock h4s and h1s. my guess is you probly have after market bulbs, of whatever color, and they most likely have a higher wattage then stock bulbs. Which probly means that if you solder your stock wires to those high wattage bulbs, it might melt your wires, cause gauge of the stock wires is real thin, and wont withstand that much heat. I know cause i ve had a lot of problems with meltin wires and harnesses back when i was using the usdm lights. So when i got my h4s and h1s, i went and got some heavy duty sockets ( plugs or harness whatever u wanna call it ) wich have a thicker gauge wiring. My lights are on a lot, and i dont have any melting at all, plus is easier to take off if you even have to swap bulbs or something.

I ve posted a lot about what i did, just do a search and type in heavy duty harness or something, my posts should come up with some pics of what i did.

yohan420 · 04-01-2004, 08:46 AM

Here's what I was told ,and I can forward you the e-mails if you wish .. can't remember the name of the guy but he made a pretty nice writeup for doing the jdm 1piece light install at hpoa.org.. I pm'd him and he gave me awesome information ..

First the misconceptions:
H4 has high/low filament in the bulb (and 3prongs on the light) .. so I should wire my high/low to the outside light and the inner one can be used as fogs - this is also how they're wired in japan ... FALSE ..

Now fact:
In Japan the high beam filament in the H4 bulb is not used. The 3rd prong (top) of the H4 bulb is not used or wired up at all in japan on the 4gen prelude. They are wired up the same as Canadian/US model 4gen's. The inside (H1) bulb wires up to the highbeam and in canada with daytime running lights ..

In short what this means is you can cut your wires going into the 9006/9005 plugs and solder them to the wiring plug/harness attaching to the h4/h1 bulbs the same way.

And yes, the corner lights are the same plugs as the JDM lights and need not be spliced.

neoekai · 04-01-2004, 11:20 AM

I am in the same boat E luder is in, I spliced my 9006 and 9005 wires to the H4 and H1 blubs without the harness. The H1 holds up but the wire that connection from the 9006 harness to the H4 blub itself keeps melting...

I tried chaning to a thicker gauge wire but it still melted, so I said **** it, i've been driving aroudn with just the H1's ...

E_Luder · 04-01-2004, 11:31 AM

Thanks for the replies.... Right now I am having difficulty understanding but that is most likely due to the fact that I haven't looked at the usdm setup yet and how it works. I'll get on it tonight hopefully and then read the posts.
If I have any other questions I know where to ask them....

THanks boyz

Grant · 04-01-2004, 12:35 PM

I took a couple of burned out 9006 and 9007 bulbs.. broke off the glass and cut the plastic down so all I Had left were the plugs..

I then soldered a H1/H4 wire harness directly to the bulb plugs.

The I just plugged it into the exiting wiring.. Clean and simple.. all the soldering I did at my leisure, seated comfortably at my desk.. and after I got the lights installed it was plug and play..

yohan420 · 04-01-2004, 12:53 PM

I thought about doing that but splurged and bought REAL 9005/9006 harness' with the leads attached. I'm just going to solder those up (rather the shop will) so no splicing of oem wires is required