cluosborne

How-to Write-up

Disclaimer: This write-up depends on the reader possessing some basic level of electronics and soldering. I'm not responsible if you blow up LEDs, your car, or yourself. This write-up is a guide, but should not be considered the end-all be-all of existence as far as LED backlighting is concerned. I encourage you to think for yourself and use good judgement.

How to convert your instrument panel lighting on a 2nd Gen RX7 to red LED (Light Emitting Diodes)

Light bulbs. They've been around since the early 20th century. Though proven technology, they're fragile and have a limited life. Light Emitting Diodes, LEDs, are solid state; no filaments to burn out or break, no fragile glass, draws less current, and lasts longer.

Mazda's instrumentation and switches; well marked, easy to read, but nothing exciting at night. Well, by switching the old bulbs with red LEDs, you change the orange to red, you draw less amps, and you don't have to worry about disassembling your dash pod to replace bulbs (at least not for a very long time). Also, at night, the color red doesn't interfere with your night vision, and it just looks plain cool.

For this project, you will need the following-

Tools:
Philips screwdriver
Flat-head screwdriver
Soldering Iron
Solder
Needle nose pliers
Multimeter
Wire cutters (optional, but recommended)
Desoldering braid (optional, but recommended)
DC power supply 12V (optional, but handy for testing out of the car)

The following tools are optional. It is for the overhead console:
Dremel tool
Hand files (for model kits)
small drill bit, 1/8 or 1/16?

Parts/materials:
35 5MM RED LEDs (Agilent Technologies HLMP-ED31-SV000, 0.43 each, Newark)
5 10MM RED LEDs (Hosfelt part # 25-339, Toshiba TLRH190P, 3.49 each)
3 5MM AMBER LEDs (Agilent Technologies HLMP-EL31-SV000, 0.45 each, Newark)
3 GREEN LEDs (Hosfelt part # 25-366, 0.99 each)
1 BLUE LED (Hosfelt part # 25-368, 0.99 each)
40 390 Ohm Resistors (Newark PART #: 94C3524, 0.39 each)
electrical tape or heat shrink tubing
white paper or similar reflective material

For the overhead console:
clear plastic (from a model or similar, optional)

Tip: I'd buy extra LEDs and resistors in case you ruin an LED or resistor or if you want to convert other parts of the interior.

Once you've gathered your parts and tools, you want to remove the switches (lights, turn signal, cruise, wiper), Logicon face, Idiot cluster, and instrument cluster. For the overhead console mod, the overhead console containing the dome lamp and sunroof switches (if equipped). Write-ups on how to remove these are documented somewhere, so I won't get into any detail here. However, the plastic trim is fragile, so be careful when removing anything.

Retrofitting the LEDs into the warning lamp cluster, switches, and Logicon are pretty easy (or at least straightforward). Essentially you are removing the factory bulb assemblies (grey, brown or black plastic sockets that contain the bulbs), taking the bulbs out of the sockets, and installing an LED and resistor.

However, there will be a few exceptions. For the turn signal and cruise control switch (if equipped), you'll need to position the LED inside the paddle shaft, and use a short length of small gauge wire-like from a ribbon cable-to wire the LED to the corresponding socket.



You could also directly solder the LED/resistor to the contacts, but make sure you know the polarity of the contacts. If you do not get the correct polarity, the LED will not light, and may actually flash when you turn the light switch off during testing.

Tip: WAIT until you've tested that ALL the lights and indicators are working first before you put everything back together. Expect to be in and out of the car a lot testing and tweaking the position of the LEDs.

Important: When working on the cruise switch, you'll have to remove a panel behind the paddle itself. Be careful because there are some small parts that you need for your SET button to work properly. Note how they came apart and keep those little parts in a safe place.

The LED circuit itself is very simple. Here's a pic of the circuit we will use, courtesy of the LED museum. http://ledmuseum.home.att.net/reserved.htm



You'll do this for every bulb that you're replacing. A resistor is used inline to reduce the current to the LED. Remember that the bulbs get about 8-12 volts DC (don't forget you can vary that value with the dimmer ****!), and the LEDs typically accept 2-3 volts DC. Do NOT just hook them up without the resistor, otherwise you could literally blow the LEDs to hell.

Now, lets get back to the basics of retrofitting an LED into a bulb socket.

This is what you should have to work with.



The leads for the bulb simply wrap around the outer edge of the socket. Just use a small flathead screwdriver to unwrap the leads and pull the bulb out. You should end up with this:

cluosborne

Now, take a resistor and stick one of the leads inside one of the holes. Then, take the lead and wrap it around the outer rim like the bulb.

Now, clip off the excess lead with the wire clippers and wrap the remaining lead around and use a pair of pliers to get the lead flush.

With that done, we prepare the LED for its installation. Referring back to the circuit diagram above, you'll want to solder the cathode lead to the resistor. To start with, bend the cathode lead 90 degrees and insert the other lead inside the socket, wrapping it like we did the resistor. Then, using the wire clippers, trim off the excess leads of the resistor and LED, leaving enough for the two to be soldered together. Then, simply solder the leads and there it is, a completed LED assembly ready to go.

You'll want to repeat that for almost all the LEDs you'll be putting in.

With the light switch and the wiper switch, the positioning of the LED inside the control ***** will require some more soldering. This is due to making sure the LEDs are positioned under the labels (the symbol for lights or wiper mode on the switch). It's especially handy to have a desoldering braid because you may goof up on the installation, and using a socket isn't feasible because it'll put the LED inside the ****, not under the label. Also, with the upper bulb, you'll want to remove the label and put a few slips of white paper inside the switch. This'll distribute the light and allow the labels to light properly.



Tip: With the switches out of the instrument pod, and connected to the harnesses, use a multimeter to determine polarity, using a marker to note polarity.

The Turn signal switch uses a single bulb, and for the best results, we'll be placing the LED inside the shaft. Therefore, we'll use a short length of wire. Just like the steps with assembling an LED/resistor into a socket, solder the leads onto the wires, and insert and wrap the wires into the socket. Then, install and test.

For the cruise control switch labels, MAIN and CRUISE, I used an AMBER LED for MAIN, and a green one for CRUISE. Just retrofitting them into the sockets and plugging them in won't fully light the labels.

Once you've determined the polarity of the contacts, bend the LED toward the label (be careful not to let the leads touch), then install the assembly in the switch. The LED should face toward the back of the label. That way, the light from the LED will be projected toward the label.

The wiper switch is essentially the same as the light switch. The trick of using white paper inside the assembly also applies here if your car is equipped with a rear wiper, otherwise it'll dimly light the hazard indicator. A red LED is also used for the hazard indicator (which shines brightly with the paper behind the LED).

For the instrument cluster, the bulbs are larger than those in the switches and Logicon. There is just one bulb that is smaller. Fortunately, for the shift-up and high beam indicators, you simply solder the LEDs in the sockets and plug them in (don't forget polarity).

cluosborne

Unfortunately, you simply can't retrofit the red LEDs into the sockets and be done with it. The light has to be diffused throughout the cluster, and the old bulbs relied on the white plastic enclosure to do that.

Some positioning inside the cluster will be needed to make the best of what light is put out by the red LEDs. I decided to use larger RED leds that are 10MM, and reportedly put out more light than the 5MM ones.

Note: After getting everything back together, I realized that the jumbo LEDs weren't necessary. 5MM ones are very bright.

Unfortunately, I destroyed two of the five I ordered. They can be fried with as little as 3V olts DC, which is why the resistor is needed.



Fortunately, I have ordered several extra 5MM LEDs, which I already know are very bright to begin with, and I still had 3 10MM LEDs left. So I used the three large LEDs to light the bottom light diffuser, and some 5MM to light the gauge faces.



Now, this entails removing the gauges from the housing and running wires inside the white housing. The gauges themselves are held on with philips screws. Simply work your way from one side to the other and place the screws you removed on the gauges so you don't lose track of which screw goes where.

Finding a way to position the LEDs for the best lighting is important because you want to have a good uniform light inside.

cluosborne

The placement of LEDs is going to be a little bit of trial and error to begin with. Since it would be a pain in the *** to wire things up, put everything back together, place in the dash and have to pull it out to fix something, I suggest that you get your hands a DC wall-adapter with 12V and temporarily wire the LEDs up. You save a lot of time and aggravation that way.

The gauge faces are clear plastic overlaid by the printed gauge face.

You can see how the white housing diffused the light. Anyway, it's a matter of placing the LEDs inside using lengths of wire, and test their positioning by placing the gauges back in place and lighting them.



Work your way from left to right, installing LEDs, test lighting with the gauges in place, and repositioning as needed.

On the back of the instrument cluster, you can either solder the leads into the sockets, or solder the leads directly onto the circuit board. The small illumination socket will have to be soldered.

Use pieces of electrical tape to cover the soldered areas and once you're satisfied with the lighting, you're done.

cluosborne

The turn signals are another problem. The green lenses are thick green plastic, which won't let enough light through. They are easily removable with a knife or flat-head screwdriver.



In order the for the green LEDs to be visible, you'll need to carefully drill out material from behind the lens, drilling larger and larger until you have a dome that the LED can fit inside. Use some super glue to hole the LED in place.

You don't necessarily have to drill straight through, but you can if you want to. Like with the cruise and turn signal switches, extend the leads with some wire and solder them to the socket. A pic of the finished product is above. Once they're ready, put the cluster back together and solder the leads to the circuit board. Make sure that you have the polarity correct.

With the logicon, you'll need to remove the face. This is probably the easiest retrofit to do as there are only two bulbs.

The backlighting is diffused and all that's needed is to place the LEDs and resistors inside the sockets and plug them in (making sure you have the right polarity of course). You will need to carefully twist the LEDs so that they're inside the socket as deeply as possible, otherwise, you won't be able to fit them. The other indicators are LEDs so there's no other bulbs to replace.

Like the switches and instrument cluster, the warning indicators are removable bulbs, and it's simply a matter of removing the cluster, disassembling it, removing the bulbs from their sockets, then putting the LEDs and resistors in their place (once again keeping polarity in mind).

cluosborne

Once you've plugged everything in and made sure every single LED works, you can put everything back together. With the lights off, the markings and labels are orange. But with the lights on, they'll change to red. The dimmer still works. The switches are especially visible during the day, but you may be disappointed by the appearance of the Logicon and instrument cluster. When it gets dark, that's when the red really comes out. There is still room for improvement and tweaking. You could find brighter LEDs or try different value resistors.

cluosborne

What's next is optional, but if you'd like to do something different with your overhead console, read on.

While I was at it, I thought it would be cool to light the sunroof buttons. Not only would they be lit from behind, the arrows in the center would have light shining through them. I accomplished that by removing the buttons from the switch assembly (they're held in place by c-clips that can be pushed out with a screw driver), and putting a piece of white paper to diffuse light.



For the buttons, I drilled a hole inside the arrow of each button, then used a hand file to shape the openings. I made clear plastic inserts using pieces of clear plastic from a model kit, cutting and shaping them to fit, then just pressed-fit them inside the holes. That was accomplished with a dremel tool, drill, some small modeling files, and patience. Two LEDs were placed under each button, facing outward.



There is no drilling needed to run wires inside the assembly, just tape them to the sides of the buttons and put it back together (it'll be a tight fit). Inside the assembly, tap the LEDs to ground, and run a wire for the illumination down the driver side A-pillar to either the switch or the illumination lead at the stereo harness.

In my case, I tapped into the instrument harness. Specifically, the red wire with a green stripe on the cluster's white plug.

Here's how it looks installed and finished:



Of course, you can also replace the bulbs in the cigarette lighter (I don't have one anymore, I replaced it with a 12-volt socket), glove box, and storage lockers. Note that the glove box and storage lamps are not controlled by the dimmer. By now, I'm sure you get the general idea of how to do it.

jsotelo

Wow nice write up.. looks good too but I'm a suka for the orange myself :-)

Icemark

You do all that and still have green bulbs in the radio???

RXciting

you need more leds around the guages

otherwise.. very nice look... i'm more of a blue person in that case though

cluosborne

Thanks

Well, the pictures aren't the best. The needles need to be lighted. You can still read the gauges, but it can be better.

About the stereo lighting, yeah I know. Maybe I can convert that or replace it with a deck with red lighting. I am planning to upgrade the stereo too. But that's going to be a ways down the line. Brakes are next, as well as fixing a few bugs.

introVert

Very nice work, man! I love the idea- but since I have already installed blue/green indiglo gauge faces.

Wish I could do the rest of the lighting in blue (my stereo is already blue) but I am stuck with orange.

Looks good!

RarestRX

Yo,


Great write up! Thanks for the time and effort to do it...

Kevin
1989 GTUs "I wish I could contribute!"

Black13B

iTrader: (1)

EXCELLENT WRITE UP!

ERAUMAZDA

awesome write up

604Ryder

bump .... is this a sticky? if not, mods u should consider it

SirCygnus

iTrader: (1)

i cant see ****.

why red when you could go with blue?

cluosborne

I know, the needles are not lit, and that reduces visibility. One of the next steps I want to take is get needles that can be lit and a backlighting kit.

Why Red when I could go with blue? Simple: blue clashes with orange, and I find that red shows through orange as red.

That is only my opinion, and it would be nice is someone came up with gauge overlays that had white lettering on a black background. THen you could run any color backlight you want that won't clash. There's still the unlit needle problem to contend with.

Unfortunately, my writeup that was hosted online was lost when my ISP upgraded their mail server. Plus, I really don't want to host it on some "Free" site that could bring about malware.

a4sport

could you email me pics?

speedy_k@hotmail.com

i can host it for you

ErikTheDead

just seeing red x's for the pictures

tried with IE and Safari

cluosborne

The images are no longer hosted.

Aaron Cake

iTrader: (1)

This would make a very poor sticky or archive post considering none of the images work...

a4sport

many photos btu here are a few...













GREAT JOB BTW! any thoughts of doing the taillights?

cluosborne

I had, but that would be very expensive, and probably illegal. The LED bulbs currently offered don't have the brightness that their incondescent cousins have. One day perhaps.

cluosborne

BTW, I agree with Aaron, not having the pics to go with the writeup makes this a poor thread to archive.

However, with the images now hosted, someone else is welcome to repost this writeup with pictures.