Please Note: The information in this guide is provided in the hope that it might be useful in researching your own lighting. Absolutely no assurance or guarantee is made that anything here is correct, factual, or moral. Any loss, damage, or legal violation -- even if explicitly instructed -- is your own fault and not the responsibility of the author.
Index
- About this page
- Comments/Corrections
- Click the pictures!
- Picture Copyright
- Thanks!
- Kit Contents
- A word about Power
- Installation
- Bench-test your new kit
- Add supplemental battery power
- Expose fusebox
- Lift the car
- Remove front wheel
- Remove front wheel well liner
- Maybe remove entire liner?
- Remove headlight cover
- Disconnect all bulbs
- Remove wiring harness
- Remove H1 Halogen Bulb
- Plan, position, mark, measure, and measure again
- Consider the HID bulb wire path
- Position and mount ballast
- Drill a hole in your precious Elise
- Check hole for grommet fit
- Clean up the mess you just made
- Don Latex Gloves
- Insert HID bulb
- Toss gloves
- Route and Seal Wires
- Connect leads
- Tap power
- Restore Lotus Harness
- Try it out!
- Tune Alignment
- Reassemble
- How Bright?
- Beam Pattern vs. The Return Wire
- What could be done to improve the kit?
- Other useful web pages
- The Proud Parents
- Lotus Elise Forums
- Useful information
- HID Vendors with H1 mounts
1: About this page
This page exists to document my own installation of HID lighting in my 2005 Lotus Elise. It was the first HID installation I have done, and I hope that by sharing these notes others will have an easier time planning a similar project.
Comments/Corrections
If you have a question you would like to see answered here, please,
send it along. If you have the answer, all the better!
If you would like to write a long email detailing how very very bad it is to use HID lighting in a car that didn't come with it from the factory, you're free to do so. Understand that the reply might be decidedly shorter.
Click the pictures!
Small thumbnails are provided, but knowing how useful details can sometimes be, each picture is linked to larger and huger versions as well.
Picture Copyright
All photos on this page (and the enlargements linked within) are Copyright (C)2005 Steve Haehnichen and can not be used
for any purpose without permission. You might find permission is pretty easy to get, but you do have to ask.
Thanks!
Special thanks to the folks on EliseTalk for their detailed help and excellent ideas.
2: Kit Contents
The Lotus Elise uses 55W "H1" bulbs for the low beams (aka "Dipped Beam"). Sensibly enough, this means the headlight fixtures provide an "H1 Mount" to socket the bulb. There is no such thing as a "factory" HID bulb in this H1 mount. Philips and Osram make bulbs for the "P32-d" base, which is a much more sensible design as bases go. The larger bulb opening makes it easier to position and secure bulbs. A factory HID option would likely use those as-is.
But for our H1 mount, several vendors will take the Philips/Osram D2S bulbs and "rebase" them to fit the H1 mount. It's important to find a good quality product here because workmanship varies.
After some research, I decided I wanted 4300K bulbs, Philips one-piece ballasts, and quality (molded) H1 mounts. I went with this kit at XenonDepot.com.
XenonDepot.com
I received my kit via DHL from Ontario Canada in lightning speed. Even with the holidays, it only took a day to arrive. The kit was nicely packed in a box with a cut-out foam shape to support the parts, and each capsule was wrapped in bubble tape. The included harness, though I didn't use it, included generous amounts of wire, a socketed automotive relay, and 20A fuse in holder.
Email to XenonDepot is answered quickly, and they seem to know their stuff. I'd recommend them.
3: A word about Power
The XenonDepot kit included a very nicely made wire harness that provides power directly from the 12v battery main and uses the existing H1 bulb socket to switch the relay. This allows the kit to draw power from the battery mains instead of the existing headlight power circuit.
Unfortunately, in the Elise, the battery is far in the back of the car, while the headlights are (quite sensibly) in the front. I could find no easily-accessible source of high-current power in the front crash structure. Arno on EliseTalk explained that there is a 50A power lead available somewhere under the dash, but running wires to it would be quite a bit of work, requiring removal of the dash top and likely drilling.
For this reason, I wanted to find out if a separate power source (with relay) is not actually necessary, meaning I could power the HID ballasts directly from the headlight circuits. This is a controversial approach, and I encourage you to do your own research before doing the same.
Power Demands

The HID ballasts are rated "20A Max"
each according to the silk-screen labeling. However, HID lighting in general takes less power than normal Halogen (incandescent) lighting. Hard numbers are hard to come by, so measurements were in order.
First, the stock headlight bulbs draw 4.5A each. There is a large inrush current as the filament first heats up, but it's very fast -- too brief to measure. With the engine off, the stock wiring provides 12.0v to the H1 connector under load -- excellent voltage, so I'm not worried about sagging below the 9v minimum required by the ballast.
The HID Ballasts draw a large amount of current when first powered on as they ignite the arc and heat the salts in the capsule. It is this startup current that could blow fuses or cause damage to underrated wiring. I measured the highest startup current when the bulbs were cold (green line on chart), and it quickly drops off as they warm up. The highest peak reading was 17A!
Restarting the HID arc while the bulb is hot takes considerably higher voltage (up to 23 kV) to ignite, but actually less current. You can see the red line in the graph showing a lower current peak after the bulb has been resting one minute off and then restarted.
This is clearly beyond the capacity of the 10A fuse.... or is it? The automotive fuses are "slow-blow", so they can take a bit more than the rated current for a brief amount of time. According to Bussmann's spec for the ATC fuse, we should be able to withstand around 17A for a full second without melting. The current spike is actually shorter than that, and the full time spent above 10A is about two or three seconds. In my sample set of two fuses, they have not blown at startup. Your mileage may vary, especially if you see subzero temperatures or have a different ballast core. I will be carrying a few spare fuses in the car, but I'm comfortable with that for now. I will say that I have heard three first-hand reports of HID installations on the existing power wiring, and none have reported power or fuse problems.
After warmup, the HID light levels off to 3.5A of current, which is a full amp less than each halogen bulb. The way I see it, a 2A alternator load savings almost makes up for the kilogram of extra weight added by the ballasts. Right? Okay.
4: Installation
Bench-test your new kit
It's a good idea to hook up all the parts on a bench, support the HID bulb in such a way that nothing is touching it (hot hot hot), and apply power to each ballast and bulb. That way you can resolve any out-of-box problems before having your car all apart and hardware in difficult-to-reach places, or now out of warranty.
After testing, let the bulbs cool completely and carefully wrap them in bubble wrap and secure with tape, being careful never to touch the bulb itself -- only the mount. The wrapping will keep them from getting touched or cracked during the handling that follows.
Add supplemental battery power
In the process of messing with the headlights, I spent some time with the headlights on and the engine off. The stock headlights together draw about 10A, which can take the edge off a charged battery in a hurry. If you take your time, and plan to take some pictures, notes, or lunch, it's not a bad idea to hook a Battery Tender or something similar to the cigarette lighter port to keep the battery topped off as you work.
Expose fusebox

Remove passenger-side front access panel (one 3mm bolt) to get to the fusebox containing the headlight fuses. (If you forgot to disarm your alarm, you will be abruptly reminded at this time.)
By pulling out the LH and RH fuses, you don't have to worry about accidentally powering the headlights and causing a short. Not strictly necessary, of course, since you can just remind yourself not to turn them on while you're working.
Lift the car
There is one "center" jack point under each door that lifts the entire right or left side of the car. Once raised, you can set blocks under the rear tire, and a jack stand or something similar under the
front lift point. Each lift point is described in the manual and marked with a blue sticker. Don't use any other location to lift, of course. Unless you want to spend even more time on your back and knees, it's probably worth the effort to lift the car off the ground a bit.
Especially if you want to...
Remove front wheel
You don't actually have to do this, since you can just crank the wheel to each side and work around the tire, but it's always easier to give yourself some elbow room.
Remove front wheel well liner

This one you actually have to do. Release the liner panel by removing three screws. The bottom two are cosmetic panel fasteners, so it's a plastic screw in a plastic shroud. Remove the screw, then pull out the sleeve altogether. The top screw is metal with a washer. Lots of dirt back there? Yeah, me too.
When you remove this panel, note how it fits in relative to the plumbing, and how the metal tab at the top end fits around the larger wheel well liner. Be sure to replace the tab side first when you reassemble.
My left side liner was missing one of the lower fasteners. I don't know if that's normal or just missing.
Maybe remove entire liner?
With the goal of easy access and having a look around, I also removed the larger wheel liner from the car. Each side is held on by three cosmetic fasteners and just tucked into the lip around the wheel arch. It comes free easily.
Note that the relay module (for radiator fan / AC) is mounted to the passenger-side liner, so you will either have to disconnect the wires, or release the relay box from the riveted mounting tongue before the liner will come free. You can reach the module through the top access port more easily if you also remove the black grill half over the radiator. The module housing does slide off the mount, but it takes considerable force.
The driver's side liner has nothing attached and comes out easily.
You may be able to get by without removing either of the large liners, depending on how you want to mount the ballast, but I didn't try to work around them. On the right side, perhaps leave the liner loose, but in place as you work behind it -- to avoid messing with the alarm.
Remove headlight cover

The three 5mm hex bolts hold down the plastic headlight cover. Note that two of them have lockwashers while one of them (topmost one) has a lock ring and a full washer.
Once these bolts are out, the entire headlight cover and molded shroud can be removed from above. Set this somewhere you won't accidentally kick tools into it, since it scratches easily.
Disconnect all bulbs

I'm all about soldering. Vampire taps, crimp-on splices, electrical tape, butt connectors, and "scotch-lok" couplers... you can have 'em. I like the solid connection and longevity of a good soldered and sealed wire. With this intent, I think it's easiest to just remove the existing wiring harness to work on it, so I'm not soldering while cowering in the wheel well.
Disconnect the H1 low-beam bulb spades, the High beam bulb connector (it's tough, but does wiggle off), and the parking light.
Make a note of which way the high beam connector goes (blue or black wire on top)
Remove wiring harness

With all three lights disconnected, you can bring the whole wiring harness out of the headlight bay. Inside the wheel well, disconnect the side light, and then unplug the big four-wire connector from the wire harness.
When disconnecting the big connector, note that it's affixed to the oil cooler housing. You can either unlatch it by lifting the small tab, or take the easy way out and just pry it free from the housing. It just snaps into place and is easily returned after.
If you prefer to use snap-on wire taps or wire nuts then you can probably leave all the wires in place.
Remove H1 Halogen Bulb

With the wires released, removing the bulb is easy. Carefully squeeze the wire clamp and release it from the low-tech `notch' in the base. Support the base while you do this, so it doesn't sproing itself into pieces.
Using a clean towel or cloth, take the bulb out of the housing, being very careful not to touch it with fingers. Any fan of
Real Genius can tell you just how dangerous dirty high-temperature optics can be.
It's a long bulb, so be careful not to pinch it while extracting, or perhaps scratch the glass on the mount. Wrap the bulb in something soft and put it in your box of Elise Parts That Have Been Upgraded.
Plan, position, mark, measure, and measure again

With the wires measured, and the ballast mounted, you will have to have some way to get the high voltage leads from the ballast to the HID capsule in the headlight. Our options here are limited.
These high-voltage bulb leads are short! Painfully so, especially with the bulb in the cavity and the ballast outside it. The Elise doesn't have a lot of unused space to begin with, much less at the front corners of the car. Measure, simulate, and test-fit before mounting.
Note the size of the HID wire couplers as well -- in this kit, they're enormous. Fantastic nice connectors, visibly sturdy and likely watertight, but I didn't want to end up with a solution that has the connectors pinched between panels.
Consider the HID bulb wire path
Someone more clever than I might be able to thread them through the existing rubber grommet that houses the wire loom.
I ran into two problems with that approach -- the grommet is positioned pretty far up the headlight cavity, which requires a few more inches of reach that I didn't have. Other HID kits may have longer leads and make this simple.
Second, the HID leads are very high voltage (23kv), specifically so that they can "arc" and ignite the bulb. The same high voltage makes me nervous about cramming the wires into a bundle alongside other wires, or even close to each other. You'd be asking a lot of the wire insulation.
Position and mount ballast

The ballast is not small, and I don't know if it's water tight, so I wanted it out of way of road spray. I haven't had good luck with adhesive tape and heavy things over the long haul (including adhesive Velcro) so rather than have it fall later, I found a place where I could sink three screws for a solid mount. Fortunately, there is such a space on each side, right up against the composite panel around the front air duct!
On the passenger side, I used three layers of the provided double-stick tape to make a 'standoff' pad and rest the ballast against the ridge on the composite panel as shown. With a washer behind one top screw, I was able to sink three good screws into the material and firmly mount the ballast. An existing wire loom passes right above it, but doesn't interfere.
The driver's side is easier, and there are vast tracts of flat fiberglass toward the front of the wheel well and behind the main liner. Both of these locations are close enough to the headlight cavity, but just barely.
The colorful smear you see on each screw is a dab of fingernail polish ("Concord Grape", I'm told) that might help keep them from vibrating loose over time.
Drill a hole in your precious Elise

Try as I might, I could not use any of the existing holes to connect the HID bulb wires, so I drilled a new one. The provided grommet on the HID bulb is very nice, but rather large.
Check hole for grommet fit

The instructions called for a "23mm" hole, but even my Costco drill bit set is not that complete. A 5/8" wood bit made a hole almost big enough, and then a little deburring with a Dremmel tool sanding drum brought it up to just the right size. I suspect the 3/4" bit would have been too large for a tight grommet seal.
Even with its generous diameter, this hole is not quite large enough to fit either one of the HID connectors through. (A better kit might use more slim connectors.) It was easy enough to remove the connector shells and thread just the wire tips through the holes. That also provided a welcomed opportunity to wet a little solder on the spade lugs, though I doubt it was needed.
Clean up the mess you just made
Carefully blow out any plastic shavings and dust, then wipe the projector lens with a microfiber cloth. Check the both reflectors for stray bits. Cleanliness is next to brightness, right?
Don Latex Gloves
While handling the HID bulb, it's important not to get finger oils, grime, or anything at all on the glass envelope. The arc in the capsule gets very hot indeed, and any contamination on the surface of the bulb could cause it to heat unevenly and fail prematurely.
A throw-away pair of proctologist gloves makes it easy to keep your sweaty fingers safely away from the bulb.
Insert HID bulb

The HID capsule, with return wire, H1 mount and leads attached, is a seriously
long bulb! If it were just a little bit longer it wouldn't fit in the mount at all. Be very slow and careful about inserting the new bulb, since it's a bit of a puzzle to maneuver it into position without cracking the frail ceramic return wire sheath or the bulb itself.
Think of the bulb as a very expensive glass firecracker with pea-sized ball of high pressure gas. Next to it is a hair-thin wire in a long tube of brittle ceramic. If either one cracks, you're out a couple bills. No need to hurry getting it into position. Make sure the rotation is correct, with the two 'bumps' on the base aligned with the two holes in the mount. In my case, the return wire faces the top the car. (More on this later)
Once fully in the mount, hold it in place and hook the pinch clamp back into place. The bulb base is thicker than the former halogen bulb, so you might have to wrestle or bend the clamp to get it to lock securely. I had a hard time getting the left-side clamp to stay closed and had to cross the two halves of the clip together. Not ideal, but it seems secure. I was surprised to see such a fragile and skimpy mounting system for the bulb.
Toss gloves
Admire your work and make sure the bulb looks right -- centered and flush in the mount. Look at it from different angles until you're convinced it's pointing straight ahead and fully seated and secure.
Route and Seal Wires

Route the bulb wires through the hole, then push and squeeze the grommet into place. The resulting fit in my car was terrific! It looks better than the stock wiring, and keeps good wire spacing between the leads. You want some slack in the wires (no tension on the mount), but not too much slack since the wire is dearly needed inside.
Connect leads

Once the wires are in the wheel well, you can reattach the bulky connectors and couple them to the ballast. Plan the positioning so that they end up tucked
next to the headlight cavity, since the wheel well liner will sit flush against the headlight mold. Some velcro or Lotus Trunk Tape(tm) can hold them up in place until you get the liner back in.
Tap power

With the wiring harness removed, it's easy to tap into the existing headlight power leads. On mine, the solid blue wire was +12v for the headlamp, with the burly black wire being ground. Double-check with a continuity tester, of course.
Solder or tap the wires to provide +12v for the ballast. Since the ballast will mount very close to the harness connector, the leads don't need to be long. I cut all but 11 inches off each one, discarding the remainder of the provided wiring in the kit.
It's easy to extract the large 'pins' from the connector itself by removing the white cover plate, then lifting the release latch on each pin to extract it. This let me slide some heat-shrink tubing over each connection, filled with hot-glue for a water-tight and strong connection.
Restore Lotus Harness
Put the bulb harness back where you found it, and reconnect the side light, parking light, and high beam. The H1 bulb leads won't be used, of course, but they're still hot. We need to safely insulate them and tuck them away, preferably where they won't rattle around, short out, or melt against the new bulb. I used some tape over the leads, and then heat-shrink tubing over the whole connector to keep it tight.
Try it out!
With the wiring in place and everything connected, you should be able to cast First Light. You (and any helpers) might want to stand away from the light itself in case it suffers an explosive setback.
You put the headlight fuse back in the fusebox first, right? That makes you smarter than me.
Tune Alignment
Once the light ignites and fills you with joy, you might want to adjust the alignment and shape of the new beam. Michael Sands has an excellent tutorial in the Sands Mechanical Museum here
Reassemble
Put back any pieces you removed, being careful to watch for interference with the new wires. Wheel bolt torque is 77 ft-lbs. Close cover before striking.
5: How Bright?
I should mention that some HID pictures were taken with the plastic (clear) headlight cover removed, while the Halogen pictures had the headlight shell in place. I can reshoot most of them once I finish assembly, but the combo (one eye each) picture will stay as it is.
Hopefully the cover shell is not a significant factor in brightness, though it might impact focus and diffusion.

The sight of the HID glow has renewed my faith in the One True Light.. there is no doubt in my mind that the visibility and safety has improved immensely over the stock halogen bulbs. I rate this project a
complete success and wouldn't hesitate to recommend it.
I've seen a lot of HID fan pages, and they always include the required picture showing Just How Bright the HID light is. With variations in cameras, exposure, and unknown processing the pictures don't really prove much at all. How can I do better?
With the help of another Elise owner, here is a picture showing the beams from my HID installation on the left overlapping with the light from a standard halogen car on the right. The standard lights have been reaimed to about the same level.
Measurements
The camera I'm using has a sensitive and accurate light meter, and manual exposure settings. While I wouldn't go counting Lamberts or photons with it, I think we can make some quantitative statements about relative brightness.
This picture shows two exposures, one with HID and one stock Halogen bulbs. The backdrop curtain is the same distance from the car, and the camera is in about the same spot at 24mm focal length and ISO200.
I chose these two pictures because each one is right at the limit of overexposure, just starting to get a few pixels "blown out" at the very brightest spot. The two photos are about the same exposure and range, but this is admittedly a subjective judgment.
The important thing is to note the camera settings required to get correct exposure! The HID bulb picture is exposed two full stops less and at a slightly faster shutter speed than the Halogen picture! Mathematically, a photographer might say the HID scene had 4.8 times the light, if you consider the two pictures equivalent in exposure: 4x for the aperture difference, and 1.2x for the shutter speed difference. Would you agree?
In a comparison requiring less faith and mathematics, here are three unedited pictures all shot at the same exposure setting -- f4.0, 1/80s (ISO 200):
It's not a very fair comparison because the HID images are overexposed -- the bright spot in the center is blown out. The Halogen picture is not overexposed and fully captured by the sensor.
6: Beam Pattern vs. The Return Wire
Alas, here is the one fly in the ointment. The H1 mount provides a small 'notch' cutout in the base where the HID capsule conveniently places the "return wire". This is the wire that extends from the tip of the bulb back to the base, alongside the bulb itself. It is insulated by a thin tube of ceramic to prohibit a premature arc of electricity outside the bulb.
As this wire is not transparent or thin, it casts a shadow on the light projecting from the bulb. In our mount, this wire is on the "top" side of the bulb, creating a pie-wedge shaped shadow of light upward. The projector housing uses a shutter to cut off the bottom half of the light from the reflector, and a single lens to focus it.
Because the lens inverts the light, the shadow ends up blocking light that would be useful. The result is a shadow area in the near-field light pattern from each headlamp. Having driven for a couple weeks with the new lights, I can say that this shadow does not impact the useful reach of the lights. It's greatly exagerated on the "flat wall" photos because the light is not spread out over a large patch of pavement. Once the car is on a flat road, the light pattern is much less distinct, and the wire shadow is largely filled in. Most importantly, the leading edge of the light, the "far" light, is full and bright. It's not a big deal, but still not ideal either.
I don't know what solution is possible for this. Perhaps a creatively-designed return wire could hook around the base of the glass capsule and then traverse the bulb on the bottom side to the tip? Maybe there's some modification to mount the bulb upside-down in the mount? Any suggestions or product pointers would be welcomed.
The Lotus Double-V

Speaking only for myself, I detest the stock headlight pattern from these projector housings. It might be all the rage in Europe, but the "Double V" factory pattern is not where I want light when I'm driving. The hard cutoff between light and dark is also less than ideal. In reflector housings, there is a more gradual transition between dark and light that serves to light distant road markers and provide at least a little light "out ahead".
The HID upgrade made the light much brighter, and lights a "wider" portion of the road, but the cutoff pattern is set by the shutter and does not change. Just having the brighter HIDs does help fill-in the center area between the lights and extend the reach both left and right. The brighter HID light also allows a bit more flexibility in aiming the lights, as the lower portion is brighter and more useful. All in all, a very worthwhile upgrade.
The rising flare on the right side of each light pattern can be removed as part of the adjustments, but this further limits the size of the beam of light, chopping off light (the angled 'tail') rather than adding back the missing part. The HID bulbs go a long way in providing more light, but improving the shape of the pattern will require mechanical changes to the shutter or assembly.
7: What could be done to improve the kit?
Here are some ideas of what could be found in an improved or Elise-specific HID kit. If you agree, then these are some things to look for in shopping.
- H1 base bulbs with the return wire opposite the notch, different than you see here. Let me know if you find one!
- More wire on the bulb please! The very short pigtails made installation more difficult than it had to be.
- If the 10A fuses don't blow, then perhaps there's no need for fancy wiring harness (relay, H1 socket, etc) -- just ballast power plugs with pigtails.
- Thin H1 base flange that better fits our skimpy pinch-fit retainer clip. Or include a replacement clip option of some sort?
- Waterproof ballast box? Depending on how much water you regularly drive in, a waterproof or splash-sealed box might be useful. The ballast power socket already looks water tight on my kit.
- Smaller grommet on the bulb leads (so you drill a smaller hole). There was no apparent need for a grommet this big (23mm?) just to pass two wires.
- Bulb-side wire couplers should arrive half assembled, so you can pass the wires through before attaching the huge connectors.
- Smaller (high voltage) wire connectors. One that includes both leads in one small connector (which disassembles for installation) would be bonus.
- Soldered-on connectors would be bonus, especially on the high voltage side. Silicone grease around the spade crimp in the connector might help ensure a water-tight connection?
8: Other useful web pages
Here are some links of interest Lotus Elise and HID hopefuls
The Proud Parents
- Lotus's own web page, while certainly the authority on the car, is rather devoid of useful information. Certainly the first place to visit if you have no idea what this car is about.
Lotus Elise Forums
- EliseTalk, the seething cauldron of Elise-oriented banter. Several of the most knowledgeable Elise owners in the world frequent the forum. It's one of the nicest online car forums I've seen.
- PureSportsCar.com is another excellent online forum for North American Lotus Elise enthusiasts.
Useful information
- The Automotive Lighting FAQ was the most useful page I found on the entire Internet regarding HID bulbs, wiring, and fixtures. Be sure to read both the page on HID and the one for projector beams It helped explain the rainbow fringe at the edge of the cutoff line.
HID Vendors with H1 mounts
- XenonDepot.com is where I bought my own kit from.
Feel free to recommend other reputable vendors for inclusion here.
Last modified: Sat Apr 23 00:58:51 2005
Copyright ©2005 Steve Haehnichen