Hi guys, I recently installed an HID fog light kit and loved how it changed my night time driving. So I want to replace my Sylvania Silverstar sealed beam headlights with some HID's to match the fogs and give me some more light output. I went ahead and ordered some H4 euro conversion housings off that auction site...


I have done plenty of searching on here and found that many opted to just use a higher wattage halogen bulb such as Hella 100/90s or Osram Hyper 90/80's. I have done some comparisons and I feel the regular beam HID would suit my needs best. I drive a lot at night, and I want the light output, and longer life of the HID's. Before I order an HID conversion for the head lamps, does anyone have any advice on how to retain the fog lights? I know the fogs are grounded through the high beam filament on certain year C4's and when you install HID's you no longer have fogs since the HID bulbs have no filament.

I was just curious if any of you who have both HID fogs and head lights have found a solid solution?

Any help is greatly appreciated!

 

Yes. I had both HID for a while, but had low beam-only headlights. The foglights are grounded through the high-beam filament, which allowed me to simply connect a resistor (10 ohm IIRC) between the high-beam slot in the car-side harness and the ground of the harness. That simulated the high-beam filament. DO NOT simply connect the two with a piece of wire, as this will destroy your headlight switch (the one on the dashboard, yes the one that costs $150 to replace. Ask me how I know)

Not sure how to work it with headlights that use both high and low beam connections. Hopefully someone will chime in with more experience.

 

Awesome info! Thanks.

What are you running now? I found vettemed's thread where he installed regular halogen osram 85/80w bulbs after he already had HID's and loved the light output of the osrams.

 

I started having problems (turned out one of the resistors came loose from the wire connecting it to the connector, but I didn't know that at the time), and just put normal halogens back in. Having high-beams is nice, even though they aren't as bright they project farther than the low-beam-only HIDs. I kind of want to put the fogs back in, but it would look weird with normal headlights.

 

Oh okay I hear ya. Well then I think I am going to try some standard high wattage halogen bulbs first. More trouble free, only downside really is that they won't last as long.


Thanks for all the input Stealth, greatly appreciated!!

 

I used a 194 bulb in place of the resistor. I also used the hi/low hid kit. And I have HID fogs.
The bulb acts as the load, and its cheap and easy to replace if it burns out. Its like a resistive fuse if you ask me.

I ran a relay for the HID fogs.

I used the "hi/lo" kit, and a 55w ballast, from fleabay. Ive had it on there for about 2 years.

To add, a 10ohm resistor will likely work, but you have to add one for the high side too if you use the dual beams. keep in mind you are passing 14.3v through 10ohm.... i=v/r... 14.3/10= 1.43Amps.... Power= v*i... 14.3*1.43=20.449watts..... so you are going to need a 20.5W resistor.... get out your checkbook.
or use a light bulb like i did. it cost $1.89 from the gas station.

 

Awesome, I heard of the 194 bulb trick but wasn't sure. Right now I am just going to run some Sylvania Silverstar Ultra H4 bulbs (60/55w) in my new housings, if they don't last very long, or when they burn out, I will pick up an HID kit and use the 194 bulb trick.

Thanks fellas!

 

you need to wire in the bulbs as if they are the headlights them selves. You only need one bulb for the low side and one for the high side.

Also, you will need to run a relay for the fogs. I smoked my factory fog light wiring from the hids all the way back to the relay (I put a larger fuse in). You absolutely need that relay to power the HIDs. I ran a 12GA wire from the fuse block by the batt to the relay, and from the relay to both of the HIDs. I also added a 20a fuse inline. Of course, I used the purple and white (gray? dont remember) as the relay turn on from the factory fog wiring.

another bit of advice... the HIDs in the fogs (880 bulbs) dont project the same as halogens, you will need to adjust your fogs with the philips screw that is on the bottom. Dont remove the silver reflector from the HID bulbs... you will blind everyone.

 

Thanks for all the pics Merlot!! Is this the same procedure for the regular HID headlights as well(low beam only?).

Is it absolutely necessary to install a relay for the HID fogs even if that is the only HID's I have on the car right now? They are the 35w version not the 55w so they should draw less power than the stock halogens, unless the initial ignite of the HID's is what fried your stock wiring?

 

the stock wiring is like 20ga wires. You will pop the fuse instantly. yes, you need a relay.

initial fire up is about 10a each...thats 20a for the draw of both ballast, not to mention the crappy wire which adds to the current. at the source you are going to see like a 30a spike and 20a or so hold till they fire up, if they even fire up all the way. And if the car isnt running, forget about them lighting up. Oh and everytime they fail to start or flicker, you can pretty much count on them failing soon after. This is for the 35w ballasts. The 50s draw even more.

and you can fry your headlight switch... or like me, i fried the transistor that regulates the dimming of the interior lights. I believe I have posted up pics of that and where to find a cheaper source (GM wants like $85 for a $0.2 part)

 

Really? Hm. I have had the fogs hooked up now for over a month with no issues. Isn't the ballast supposed to limit a 35w draw and nothing more? Wouldn't I be popping fuses left and right if it was drawing enough power to ruin the stock wiring? I could have sworn I read on here from a few people that the stock headlight switch was pretty durable even with a lot of draw being put on them. I'll take your word for it, I just don't want to clutter up my engine bay more than I have to.

 

I have had the HID fogs hooked up now for more than 2 months with no issues at all and i dont even use the headlights anymore...
Best mod for 100$ so far!

 

A sometimes overlooked issue with HIDs is the increased voltage produced by the ballasts. A separate direct ground works great for eliminating undesired current to components. If you use HID lows with the stock wiring, the High beams will glow when you first turn on the headlights. A separate ground direct to the frame is a good fix.

 

Just an advanced component level electronics tech, with 3 years of HIDs on my C4, offering the best advice to other corvette owners. Your car, your choice.

35w is the wattage provided to the bulbs. The ballasts consume much more. On startup, they draw about 10A. Continuous draw is around 5A.

Power=P
Current=I
Voltage=E

P=I*E

According to your theory about power consumption/regulation:

35w=I*14.3v
2.44755245=I

So if this is true, prove me wrong... Go out and put 5A fuse inline with your HIDs. Did the fuse blow when you turned on the lights? Of course it did. Try a 10A?


Let's think about things a bit more realistic. Power is lost in any electronic device. So already we know it takes more than 35w to power a ballast. On start up you can not only assume it takes more to power to start heating up a bulb, you can also hear most of these ballasts screeching with RF on warmup. So let's assume 35w is the average power sent to the bulb, assume there is about 10w lost in heat, conversion etc, and a couple watts lost in wiring. Lest we not forget the massive amount of power lost on start up.
Lets say we are at startup, the bulb needs about 60w to get nice and toasty, we're losing about 8w in the ballast as heat and changing 14.3vDC into AC and stepping it up to 17kv, and the factory wiring is crummy and about 16-20years old (-2w). And let's be practical, and think about this in a typical car that is not running. So battery voltage available at the fog light connector is 11.7v (this is generous)

60w+8w+2w=70w

P=I*E
70w=I*11.7

5.98290598=I

If you have two ballasts (one for each light) you are at 12A of power draw for the 15-45sec of warm up time. What's the stock fuse rating? What is the size of the factory wiring? Are we going beyond the ability of the original design? What's that tiny fog light relay in the hush panel rated for?

Guys, I don't mean to be a dick about this, but I beg you to stop and think about things.




These ballasts are cheap china made crap. I have about 12 of them opened up and two on my desk at work. There are about 4 designs of these and they are all the same. They are worth about $9 each if you buy them in bulk. If you hunt eBay, they can be had for under $30 for a pair. If you paid $100 for ballasts and bulbs, you got hosed.

You can find more info if you do some research HIDplanet forums, and other similar places.

The best source for quality parts is from http://www.theretrofitsource.com

 

To add clarification... I'm talking about the fogs... Not the headlights. The headlight wiring is sufficient for HIDs.

 

Fast- That is great, any plans for the headlights?

blr33439- Interesting I will keep that in mind.

merlot- Thanks for the clarification, wasn't trying to challenge your reasoning in any way. You can't argue with your math, field of study, and first hand experience with melting the stock wiring. So I Appreciate the input, and I know there are a handful of members on here who have fried something as a result of improper HID installation, but there are dozens more who have installed the HID Fogs with no issues. Running a relay isn't too hard from my limited understanding so I may just do it. And thanks for the clarification on the headlights, I was wondering if you also ran a relay for those, good news there.

 

Just wanted to give a little update. I ordered the bi-xenon kit from ebay seller "supervtec." It is the H4 35w/6000k system. Only takes 3-4 days to arrive.

http://www.ebay.com/itm/BI-XENON-HI-...item4cf153354c

I wired them in using this DIY thread.

http://forums.corvetteforum.com/c4-t...with-pics.html

The install was very straight forward and didn't take very long. It uses a relay type system so it draws power directly from the battery and uses the same ground as the factory lamps. Very clean and professional looking under the hood. Everything works as should. The fog lights work as well so no need for a resistor or 194 bulb. The hi's function perfectly and the fog lights go off like they should. So far I am very happy with the outcome, the light output is a night and day difference over the H4 silverstar ultra bulbs. I did a quick vertical aim but still need to do it per the FSM to get it perfect. The right side housing needs to come down just a hair. Had a friend drive towards me on a two lane highway and said the light was aimed down and out of eye sight.

A few pics

Lows


Highs

 

I don't think the photos work anymore.

Could you elaborate which wire goes to which for the wiring of your 194 bulbs? Currently I have a 60ohm "50 Watt" resistor wired in between what I think are the low beams and ground on the factory three prong headlight female plug. I think I hooked up to the green and black wires. Did it do that correctly? I am planning on doing your 194 bulb trick for both low and high beams, but I don't know which wires to connect together on the factory three prong plug. One bulb connected to black and brown, and then one connected to green and black? Is this correct? Thanks.

My headlights go up and down and turn on fine, but I am getting the high beam indicator light on in the dash when I turn on fogs only or dogs with low beams. I read that I need the resistor (or bulb) ok the lows to operate the gear to raise and lower headlight units correctly, so I am assuming I had the resistor hooked up to the low beams currently.