Comprehensive Lighting Modification Thread

suprarx7nut author
Nov 10, 2006
This thread is intended to answer basic questions about the lighting set-up in the MKIII. I have completed the gauge lighting and climate control using LED's and a PWM dimmer. The first two posts will be continually updated as I complete all my lighting throughout the car.

Gauge Cluster Lighting





Many members have used LED's from with success. These LED's are simply "plug and play" and require no extra modification.


Simply remove the old bulb and replace with a new LED bulb.

When using the 5 WLED bulbs the oil gauge may appear dimmer than the other gauges since the oil gauge is lit by only one #74. I solved this COMPLETELY by placing a small section of aluminum foil over the bulb, directing most all the light onto the gauge face and its clear plastic "light carrier".

Light dispersion is very important for the gauge cluster's appearance. "Hot spots", where lights can become focused, are your enemy. When using LED lights, hot spots can be a problem. This can be fixed by using "wide angle" LED lights. These lights put more light out the sides of the bulb and help to prevent hot spots. Using the 5 bulb LED's from superbrightled can lead to hotspots directly in front of the bulbs. (3 and 9 O'clock on the speedo and tach especially) I solved this by painting the tip of the top bulb black. Using just these bulbs will tend to make any painted needle appear dimmer. Beware.

Another method is to paint the incandescent bulbs. This is a cheap and relatively easy way to change the color, but care must be taken not to overcoat the bulbs making them too dim.

Climate Control Unit

29 - T1 (3mm)

13 for the indicators
16 for the buttons

Using the 3mm LED's from superbright made my climate control insanely bright. If I were to do this again, I would use an LED with a lesser MCD rating. Mine were rated at ~4500 mcd and that was way too much. Looks neat by itself, but it is blinding at night on a highway.

CC unit disassembled, showing the Temp display and the button lighting LED's:


Here is the backside of that same plate. You can see the solder joints which you will need to de-solder and then re-solder your new LED's in place:



Blue: DA04-11PBWA/A
Yellow: DA04-11YWA
Red: DA04-11EWA

You need this standoff, or it'll look sunken in the CC unit:
DIP: DigiKey P/N: AE8916-ND

You need window tint to replace the factory green tint. Without the tint it's way too bright and will look super cheap. I got a big roll of tint from a local tint shop's scrap bin.

Interior Lighting

All bulbs here are awaiting confirmation. If one is incorrect, notify me via PM or post here.

Location_______________Bulb Type

**Bulb tpyes that I am CERTAIN of are in BOLD

Key ring _______________#74
Driver's footwell_________#74
Overhead lamp__________BA9
Cigarette lighter ________#74
Ash tray_______________#74
Driver's window switch___3mm (T1) x2
Glove box______________#74
Vanity Mirror___________#3022?
Door Panel_____________#3022
Hatch light ____________#3022
Exterior key ring ________ 2mmx5mm according to Ivan (iruyle)
Dash Buttons___________12V incandescent << Need to integrate resistors w/3mm led.

Total required:

#3022____1 <-----Use High Power LED's if you want it to be any brighter than the stock bulb
BA9______2 <----Use High Power LED's if you want it to be any brighter than the stock bulbs

Changing the dash switch lighting is far from plug'n'play.

Here's how I did it:

-Remove switch from panel
-Remove rocker part of switch (front face that you touch)
-Remove nasty green filter by punching out the part of the face that lights up. We'll call this the "icon".
Defroster filter shown below

-Remove filter layer by prying the layers apart with a jewlers screwdriver or a razor.
-No more green. (Yes!)
-Replace icon with super glue or the like.

Swapping in LEDs:
Since the old bulb was incandescent and ran on 12V, we need to alter the voltage your new 3mm LED will see. This is accomplished via resistor(s).
Common 3mm led's will require something around 2-3V. Careful! Too much voltage/current will blow an LED immediately. For my white and red LED's I needed about 500 ohms resistance.

Use this equation; The resistor value, R is given by:

R = (VS - VL) / I

VS = supply voltage (12-14V)
VL = LED voltage (usually 2.7V, but 3-4V for blue and white LEDs, check your LED's spec sheet)
I = LED current (e.g. 20mA), this must be less than the maximum permitted

Easy, right? I hope so. If not, you may want to revisit high school math/physics.

Ok, so now you know what you need. Go to radioshack or any other electrons parts retailer and get some resistors. Time to solder...

Making the circuit within the switch:
Remove the backing to the switch. It is snap fit and requires careful prying.
Remove old bulb from rubber socket. Notice how the light is fed with voltage.
Insert new LED into rubber socket.
Cut the resistors down so only about ~1/2" of wire extends from the resistor. Now I needed to use two resistors in series to achieve my target resistance, so I needed to combine two.
Solder the resistors together and to the LED, making one lead of the LED really long. Use shrink insulation to enclose the wiring mess you made.
Like this:

Now you need to connect this to the other terminal of the rubber socket.

Insert back into switch panel. Test which way it needs to go. Only one way will light because LED's are polarized. Dur.


This was the fog switch, but I did the hazard and defroster the exact same way.


This is actually an easy one. Remove the window switch from the door handle. Disassemble the switch until you get here:

Now remove the tan circuit board. Desolder the LED's, then resolder in the new 3mm (T1) leds.

Mine ended up a little bright, but not distractingly so.

DIMMER wiring:


I wanted to have control over the climate control to get it a little closer to the dash lighting and THEN be able to control both together. I ran into a problem: The climate control uses a voltage regulator or some controller within itself that cuts out if the dimmer signal going in is adjusted either with a pwm or the regular dimmer. DAMN.

My current set-up is as shown above and allows me to control the climate control with the stock dimmer to dim it down to it's lowest point. From here I can dim the dash and the cc unit by using the PWM dimmer I bought from superbrightleds. This works well, but it'd be really nice to tap into the cc unit wiring. CRE had told me that he found the true dimming line within the cc unit, but I'll have to ask him to remind me of that wire.

Here's my current set-up:



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suprarx7nut author
Nov 10, 2006
LED Needles writeup

Well here it goes. This took a ton of labor to perfect. I'm no wiring genius and until this my circuit prototyping experience was practically zero. I'd worked on basic breadboard projects in my electronics 101 engineering course, but that was about it.

First, for a perspective, these are the SMT LED I'm dealing with.

They are far from the smallest available, but are plenty small for this project. They are a 1206 package. Digikey part number 160-1167-1-ND. I got 50 of them for under $5 a year ago thinking they might come in handy at some point.

This is my power source. 8 1.5 AA batteries in series. That makes 12V for those scoring at home.

And just for shits, a picture of my garage. Nothing special, but I love it. It's a rental, but if I owned it you'd see finished walls, epoxy floor and wall storage galore. But alas, I'm still young so home ownership isn't under my belt yet and my garages are pretty basic.

So the gauge lighting concerns starts with the fact that once you update the face lighting with LED's, the needles fail to glow as brightly, especially if you pain the needles. I wanted a crisp white face and deep red needle. This means White leds in the face and red SMT (surface mount technology) LED's or SMD (surface mount diode). Mine were roughly 1mm tall which means they can fit between the gauge face and the component behind the gauge. The amount of clearance available varies from gauge to gauge. The speedometer and oil pressure gauge likely have the least amount of clearance. They were the most difficult for me. The easiest is probably the tach.

So onto design. I started with a search for a substrate. Having no experience with circuits I was lost. All i knew was I needed something very thin and something that I could stick some LED's to. To try my plan I and to make sure the LED's would light the needle correctly, I started with cardboard and an old credit card. LED's worked and lit the needle perfectly. The cardboard and/or credit card as a substrate was a horrible idea, but you probably could have guessed that.


Somehow I lost a ton of photos which would have shown exactly how I made each circuit board. At some point I'll add them back in if I find them. For now, I'll have to skip some pictures and bore you with words.

Before actually doing anymore building I measured the hell out of the gauges and the mounting areas. I measured everything in inches and to an accuracy of 0.01". I wasn't able to hold that same accuracy during the build part, but the accurate measurements were definitely helpful. The only gauges that were similar were the water temp and gas gauge; and even those had minor differences if i recall correctly. Once I had all my measurements I modeled the baords I had in mind in SolidWorks (CAD).





The above drawings should be right, but I had to make adjustments and I'm not positive I went back to edit all the cad files. So use that info at your own risk, lol.

Once I had everything modeled it was time to start building. A pair of locking foreceps was key to soldering with the SMD's. My soldering iron is a basic POS and made this more difficult that it could have been with a good iron. I found some proto board about 2 inches square and 2mm thick. I used a dremel to cut the boards into the correct size and then proceeded to start the wiring. The pieces all needed to be pretty thin. The speedo especially has very little clearance and has a very delicate piece of the gauge directly underneath where the LEDs are mounted. This means you have to be very sure your LED inserts will not touch the instrument. The needles on all gauges are very delicate. Any slight rubbing means the gauge is worthless and you have very little margin for error.

I had a great picture of the speedo showing exactly how tight it is, but I seem to have lost it. Imagine a very small space....

The smaller gauges all have a light guide system that relies on the face lighting to carry into the center of the gauge face, where a semicircular extrusion of clear plastic grabs the light and throws it out onto the needle. Clever design, but unfortunately it wont work with what we're doing and you need to cut it off. I used a dremel and was very, very careful.

Below you can see the difference between pre 89 (my prototype dash) and 89+ (My actual car). The pre 89's have a TON of space for the needle to catch light from below. The 89+ on the left have just a small square (green arrow) to catch light for the needle. This affects how much light is needed and determines whether or not you need to drill out the gauge plastic to let more light through. My proto board (pre89) was fine leaving the plastic backing alone, but on my actual car (89+) I had to drill out the plastic entirely underneath the needle.


This is what I'm talking about:

Left alone:

Drilled out:

In the picture above you can see how the LED's are mounted. It's pretty basic, really. You just need to measure everything and know where you need to center the LED's.

Here's the Speedo finished:


And here's what the board looked like more or less when I was done with the speedo. I had to use my dremel drill press as a mill and mill a channel for the wire. The clearance was so low that the board plus the wire (22AWG) was too thick. The problem with the speedo is that you cant have anything hanging down under the board, so the wires cant be underneath, they have to be on top.


This is the speedo unit. That coil is the gauge and is incredibly sensitive. Nothing can touch it.

Just for shits, here is the oil pressure gauge. I dont understand how the gauge actually moves, but the whole thing is so flimsy I just cant grasp how it could be very accurate.


Here is one of the small gauges after already having shaved the bottom of the needle base. Clearance are very, very tight. You want to keep this clearance minimal so you have less light escaping from the center of the gauge. Light bleed will be noticable when you use two different colors for the needles vs gauges.






Under Construction - This section will cover the "headlight rewire", "foglight rewire" and "H4 conversions". All of these have been covered plenty, but since this is supposed to be an "answer all" for lighting, info will be provided.

The headlight rewire I am planning on covering here is from Daniel Stern lighting. It involves using a standard Bosch relay to allow your headlights to be powered straight from the battery, INSTEAD of the shoddy, 20 yr old, small diameter stock wire and the switch on the steering wheel stalk. The benefit is that the voltage your lights see, will be much higher, in theory. I will be measuring my results to see how much a difference it actually makes.

Info on relays and the whole purpose behind this rewire:

[Summary will be here for those of you who dont want to read the pages of text in the above link.]

The foglight rewire I will focus on is the one which allows you to turn on the fogs WITHOUT the headlights being on. You can also wire the fogs to use a relay, instead of the stock wiring, which I will cover as well.

Most this info will come from Dylan Wiggans' write-up. [Cwapface]


After seeing a few other members with the Lexus fogs from the 92-94 ES300's I tried them myself and made a bracket to fit the MK3. They make a HUGE difference. Videos of the lights are here. After I do the relay rewire they should be even brighter.

Caution: These brackets do NOT work with the stock IC piping. You'd need to mount them like mattsplat72 has or cut your bumper or something.

Plug and play brackets and other hardware available in my sig link.

Finally the H4 conversion, which some say to be a safety upgrade involves swapping out the stock sealed beam headlamps for higher quality, H4 housings which allow replaceable H4 bulbs to be used. Hella and Cibie E-codes have a great reputation for this procedure among our cars and I will hopefully be installing and documenting the differences with a pair later this year. The Cibie's are nearly twice as much, but supposedly give a better high-beam pattern. :dunno:

This one is very straightforward. Until I do my own this may only have links to vendors who sell e-codes.
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7M-GE + MAFT Pro + T = :D
Oct 24, 2005
Denver, CO
That's him... that's my boy... <CRE wipes away single tear>... I knew him back when he drove a Honda... <CRE buries face in hanky>

suprarx7nut author
Nov 10, 2006
CRE;1082429 said:
That's him... that's my boy... <CRE wipes away single tear>... I knew him back when he drove a Honda... <CRE buries face in hanky>

...that fucking honda. :nono:

Didn't you say something about sleep? :sarcasm:

I need more pics for this thread. It's annoying trying to find someone else's pics that happen to include what I want. Maybe this will motivate me to do mine sooner, but I can't decide on a color...

suprarx7nut author
Nov 10, 2006
plaaya69;1082501 said:
Good Thread. How does the other two stock gauges look?

The oil gauge is one that I hear people have trouble with. It is lit by the one #74 bulb, so I guess when you use brighter bulbs(5WLED) the oil gauge can look dimmer than the rest. I will try to alleviate this when I do mine. I want it to look near perfect if I do it at all.

rtrdpenguin;1082518 said:
Awesome! It' about time someone did this =) I remember having to dig through quite a few pages of posts to find out what LEDs I needed.

Yup, me too. I estimate I've probably spent 3-5 hours searching through all the LED lighting threads to try to find the needed info. Hopefully when this is done, it will allow people to get all the info they need in one, easy to find, place.

lilazni3uoy;1082527 said:
nice picture :love:

Figured you might like that ;)

Do you have any other pics of the dash? I'll resizing and cropping all the photos anyways, but I'd love it if I could get one pic that included all gauges.


AEM Powered
Apr 1, 2005
NoRCaL and SoCaL
actually i did not take one, but i'll probably take one tomorrow at work, to get the whole gauge, as as suprarx7nut stated, the gas gauge is the hardest to light, but you guys that are trying to refer to that picture above, those are just not led's so even if you did do led conversions it will not be that bright

suprarx7nut author
Nov 10, 2006
lilazni3uoy;1083107 said:
actually i did not take one, but i'll probably take one tomorrow at work, to get the whole gauge, as as suprarx7nut stated, the gas gauge is the hardest to light, but you guys that are trying to refer to that picture above, those are just not led's so even if you did do led conversions it will not be that bright

I was actually referring to the oil pressure gauge being dim. Although with your unique set-up, the gas gauge does seem a little weaker.

First post updated.


Permanently Banned
Nov 26, 2007
Hayward, CA
I have been contemplating replacing the bulbs in my cluster with LEDs to match my White/Amber ProSport gauges. I also need to replace the plastic cover since mine is foggy.

This thread helps a lot.

Also in for headlight rewire!


Boobs/Boost, my favorite
Jun 13, 2006
Los Angeles
The vanity lights (the ones on the visor) are 3022 Festoon bulbs..

the door courtesy lights are also the same, and so is the rear hatch light..

the rear license plate lights are 67's...

The Dude

no more supra
Apr 5, 2005
Okinawa, Japan
ILikeCarsYesIDo;1084521 said:
I have been contemplating replacing the bulbs in my cluster with LEDs to match my White/Amber ProSport gauges.
Ditto, can anyone confirm whether either the red or amber leds from more closely match the prosport "amber" gauges? The gauges themselves look a lot closer to a plain red than an amber color to me.

suprarx7nut author
Nov 10, 2006
RazoE;1084531 said:
The vanity lights (the ones on the visor) are 3022 Festoon bulbs..

the door courtesy lights are also the same, and so is the rear hatch light..

the rear license plate lights are 67's...

Thank you!!! I think I'm going to try to add a light to the rear hatch. Having just the one is weak.

suprarx7nut author
Nov 10, 2006
RazoE;1084906 said:
get a 4-LED 3022 from, trust me it's bright...:aigo:

Ya I was planning on trying one of the high output LED ones either way. I just think it'd be neat to make an LED light strip that attached to the back of a seat or something. We'll see if I ever get around to it....

Thanks for the subscriptions guys, it'll keep me motivated to get this thing compiled and get all my own lighting stuff done. :)