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DIY / How-to – ST3 HID Bulb Swap: D8S -->D3S

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195K views 299 replies 72 participants last post by  chefboyarie  
#1 · (Edited)
Along with my the improvements I’ve made to my fog lights, I’ve also been looking around to upgrade my headlights. For those who have been doing any research at all, you are probably well aware that the HID system in the ST3 is both underpowered when it comes to output and wattage, but also very weak compared to the OEM systems that are avilable today. From my understanding, Ford decided to go the route of a “green” design and use less power (25W vs the standard 35W ballasts) and also wanted to say under the U.S. requirement of “anything over 2000 lumens requires auto adjustments and washer sprayers” so they stuck right at 2000 lumens. What that translates to is HIDs that are basically the same output as halogens, but called HIDs for marketing purposes (in my opinion). Anyways, I thought they sucked after having my last 3 cars with HIDs so I wanted to make them better.

I’ve been poking around the idea of a complete retrofit, swapping out for new projectors, clear lenses, and higher wattage ballasts and bulbs. However, I don’t have the bulbs (pun intended) to cut apart my $4K worth of leadlight housings I have to “give it a try” at this point and while I am still waiting to hear back from some retrofit companies, I wanted to see what was possible from a wattage increase by itself. Now the D8S bulbs that come from the factory are very unique, only being used on a few Ford cars and all with the 25W ballasts. No aftermarket setups available at this point. Dang, need to move on to option two. If you look at the back of the headlight housing, all of the bulb sizes are listed that fit into the headlight assembly. For the HID’s, it mentions both a D8S bulb and a D3S bulb. The D3S is still a Hg free (murcury free) bulb, but it is a little more widely used and also has much higher outputs. Turns out that the D3S bulb can be used in the housing with just a simple modification which is about 15 seconds worth of effort. This option shows some promise, now it was time to see what was available out there.

I started poking around on the HIDplanet forum as well as on the “Headlight Junkies” page on Facebook and lucked out with finding someone selling an OEM Osram (same company as our HIDs) 35W D3S bulb/ballast setup out of a later model Audi. Seemed to fit just what I was looking for: 35W system, D3S bulbs, 3400 lumens of output… Perfect! Hit the guy up, sent them out a day later, had them in my hand within the week. Ended up paying about $180 shipped. Might have been able to get them for a little cheaper, but wasn’t really worth the battle as I have no idea what they should have been. They were OEM, working, and fit everything I was looking for. The ballast info is posted in a picture down below, but the bulbs I picked up were 66340HBI bulbs

Now that you have the back story, here’s how you can do it to your car (I take no responsibility for messing anything up on your end. It will still require you to do your own research, but this is my story and how it worked out for me).
 
#89 · (Edited)
Excellent, that part number is much easier to find and is much cheaper. Theres a half a dozen auctions on ebay right now that include bulbs, cables, and ballasts.

I've been compiling some notes on the different 35w Osram ballasts that might work for our cars that I've been seeing. Here is where my notes stand currently.

Code:
Osram Part No.	Suitability	Power	Trigger wire	Addntl Part No.'s	Label color
35XT6-A-D3	POSSIBLE	3 WIRE	?		A62941COODG (Osram)	White
35XT6-B-D3	POSSIBLE	3 WIRE	?		A71177E00DG (Osram)	Green
35XT6-S-D3	YES		3 WIRE	NO		A71154400DG (Osram)	White
35XT6-L-D3	NO		4 WIRE	YES		A57082B00DG (Osram)	Green
35XT6-7-D3	POSSIBLE	3 WIRE	?		A62479C01DG (Osram)	Green
35XT5-2-D3	YES		3 WIRE	NO		7L7Z-13C170-A (Ford)	White
35XT5-7-D3	NO		3 WIRE	YES		8A5Z-13C170-A (Ford)	Green
There seems to be some sort of correlation between having a green label and having the Remote Trigger wire. Which reminds me, I've been doing some research on HIDPlanet about the remote trigger wire and it seems that the ballasts that include option have one positive power wire (brown) that is on all the time to power the ballast, one ground wire (black) in the middle, and a low current switched positive power wire (blue) that simply triggers the ballast to turn on (and pull power from the always-on wire). I stumbled on a photo on HIDPlanet where someone just hooked both the trigger and power wire together to the power wire from the harness for an 35XT5-7-D3 ballast so there may still be hope for getting those ones with the remote trigger wire to work as well.
 
#112 ·
5

So to update your list here - I have the 35XT5-7-D3 and they work great for me. I bought them from a forum member that used them for 1.5 years and I've had them on for 4 months or so with no issues. You just have to add the jumper wire.
 
#91 ·
Keep us posted on how it works out!
 
#96 ·
Alright, these were almost a direct bolt in except for a few minor differences than the bulbs that people have used.

1. The ballast already lines up with the Focus ST ballast and no removing of the chip was needed.
2. The hardest part was turning that stupid plastic ring to secure and unsecure the bulb.
3. I had to modify the housing slightly to get the right angle plug to fit, I didn't really think hunting a straight cord was worth the effort. Since the part being modified is still in the housing and sealed it was mostly cosmetic inside modifications that no-body sees.
4. If you notice on the blue line bulb which is stock the square holes line up but the small semi-circle does not. That was preventing me from not having to modify the bulb at all to get the ring to slide around and lock the bulb in place as on the housing that is flush on the housing and needs the indentation to allow the blub to seat firmly.
5. Waiting till dark to compare. I did check for light and it does light up just not sure on angle during the day.

 
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#97 ·
Alright I took a dusk pic. After this I went ahead and did the other side. You can really tell the new setup is outputting more light and this is with junkyard ebay bulbs from a Jaguar that I don't know how good they are.
I am really sure that a nice set of bulbs would be even more difference like the Phillips extremes. Now that its d3s more options are available. Total install time was maybe 20 min per side.
 
#98 ·
Alright I took a dusk pic. After this I went ahead and did the other side. You can really tell the new setup is outputting more light and this is with junkyard ebay bulbs from a Jaguar that I don't know how good they are.
I am really sure that a nice set of bulbs would be even more difference like the Phillips extremes. Now that its d3s more options are available. Total install time was maybe 20 min per side.
View attachment 109267

That's a HUGE difference. I just don't know where to find proper ballasts to do this conversion.
 
#102 ·
The biggest difference in the ballasts that have slightly differnet wiring is just that they have a 3rd wire (a turn on wire) that has to be wired in by simply clamping it on to the 12v that's already there. It's really simple.

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#108 ·
I compiled some of my notes about ballast part numbers here that might help. I did quite a bit of searching and I couldn't find anyone that had installed 35XT6-A-D3 ballasts in their ST3 HIDs. I have a decent hunch that they will work but as far as I'm aware that is still unconfirmed.
 
#110 · (Edited)
So none of the options discussed in this thread are really plug and play. You probably need to go back and take a through read of the very first post. The person in the previous post just told you that no one has tried the variant of ballast you bought. At best you find ballast where the internal parts match the bolt pattern of your ballast's internal parts, then you swap the internals into your stock housings. You're doing this because the external mount up patterns don't match up and you can't bolt it to the headlight housing. If you find one you can do this with - Which is most of the OSRAM ones, then you have to figure out what the ballast needs to supply power to the bulb. That process may take some testing using a multimeter. Several of the ballasts need 12v, 12v switched, and ground. The stock system only needs the 2 wires. So you if you got a 3 wire one you have to jump a wire from the 12v switched plug to your stock 12v wire.

After you get the ballasts sorted out then there's the bulbs. The d3s bulbs don't just fit in our stock housings as is. You have to dremel out a tiny notch in them to make them work.
 
#113 ·
Start here -
https://www.theretrofitsource.com/components/bulbs.html

There's 3 options there for d3s. The $70 ones would be better than ebay ones, but If you really want to see a difference you need to look at the OSRAM OEM ones at the least.
This is the sort of difference you can see with the OSRAM ones -
 
#116 ·
Also here's both ballasts together. See how the stock ballast uses a 3 bolt mounting pattern and the other one uses a 4 bolt mounting patter. But the internal parts both use a 4 bolt pattern. So they can be swapped.
 
#117 ·
Excellent! Thanks for sharing! So it sounds like the only requirement to make ballasts with the trigger wire work is that you need the original plug which you then just jump the 12v switched to the 12v and you're golden.
 
#118 ·
You don't need the original plug. The wire in the lower left of the first image above can easily be made from common stuff at Radio Shack. Pin connector, wire, clip on splicer.I think you may even be able to find all of this in your normal Auto Parts store...
You just push that pin connector into your stock plug where the red cap is.
 
#129 ·
No one is responding because you keep asking the same questions about the same info that is already here - no one is going to spoon feed you stuff like this man.
On the very first post of this thread the last pic has a detailed image of the 2 bulbs side by side along with info about the notch that needs to be cut. Please read that.

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