How to Install LEDs Into your Dash
Project Started: January 2002
Project Completed: January 2002
Project Update: This project was completed back in 2002 before they sold 12V wedge LED drop in replacements which make
converting your dash to LED backlighting much simpler. I recommend purchasing these LED 12V 192 wedge base bulbs, you can pick
them up at the following sites.
http://www.superbrightleds.com/
http://www.ledlight.com/
This tutorial is still useful to see how to remove the dash, etc.
Here is a picture of the completed dash lite up:
Click on picture for bigger view
NOTE: I only used one 3000MCD LED per socket. If two were used it would be much brighter. I highly recommend using more
then 3000 MCD per socket, discussed below.
Terminology:
LED - Light Emitting Diode is a semiconductor device that emits visible light when an electric current passes through
it. Most LEDs produce light at a single wavelength. The output from an LED can range from red (at a wavelength of approximately 700
nanometers) to blue-violet (about 400 nanometers).
MCD - A measurement of how bright a LED is. LEDs intensity is rated in MCD, this is a rating of micro candle power
or micro lumens. A 1000 MCD LED is the same as 1 candle power or 1 lumens.
Resistor - A resistor is an electrical component that limits or regulates the flow of electrical current in an electronic
circuit. (is to be used to lower the voltage)
Ohm - The ohm is the standard unit of electrical resistance in the International System of Units
Polarity - Polarity is a term used in electricity, magnetism, and electronic signaling. Suppose there is a constant voltage,
also called an electric potential or electromotive force (EMF), between two objects or points. In such a situation, one of the objects
or points (poles) has more electrons than the other. The pole with relatively more electrons is said to have negative polarity; the
other is assigned positive polarity. If the two poles are connected by a conductive path such as a wire, electrons flow from the negative
pole toward the positive pole. This flow of charge carriers constitutes an electric current. In physics, the theoretical direction of
current flow is considered to be from positive to negative by convention, opposite to the flow of electrons.
Q and A's:
Q) Do LEDs burn out?
A) Yes and no, It will take them an extremely long time to burn out but it can happen much faster if there
is a voltage spike or you are putting too much power into them. You should not have any problems with them in your car if you
do the resistance calculations right. The average rated life span of a LED is 100,000 hours.
Q) How expensive are high output LEDs?
A) LEDs are becoming cheaper all the time. When I preformed this modification back in 2002 I paid
3 dollars for each LED. Now you can get 100 high output LEDs for about $20.
Q) Will this work on a 90-92 Camaro?
A) It seems to work on the 90-92 dashes from what I have heard from others but I have never tried it myself.
Q) Is there any benefit of having white LEDs over "white" stock bulbs?
A) Yes, Stock bulbs produce a yellowish orange color, which does not look good. White LEDs produce pure
white light.
Q) Will the stock dash lamp dimmer work with LEDs?
A) No the dimmer will not work; The LED’s will turn off when you turn the knob.
Q) How bright of LEDs should I buy?
A) I recommend as a minimum 5000 MCD. If you cannot buy LEDs that bright you
use two LEDs per socket.
Q) Which lead is the positive lead on a LED?
A) The positive lead on almost all LEDs is the longer of the 2 leads. Also on most LEDs there is
a notch on cathode (negative) side of the LED.
Q) What should I look for when buying LEDs?
A) There are a few things that are important when picking a LED. Here are a list of LED specifications
and what they mean.
- LED Size: There are a few standard sizes, "packages", LED come in. The most common 2 are 3mm T1 and 5mm T1-3/4.
I recommend using T1-3/4.
- Typical Vf@If(mA): This is a rating of voltage you should run the LED at and how much current it uses at that voltage.
- Typical @mA: This is a rating of the light output at a given current. The more current you put into a LED the more light
it will produce. Do not run a LED over it's recommended current rating or you will greatly reduce its' life span. The typical
current rating of a led is 20mA.
- Wavelength (nm): This is the wavelength (color) of light the LED puts out.
- Viewing angle (degrees): This is a measurement of how narrow or wide the beam of light coming out of the LED is.
For a backlighting application like I am using it for, the wider the better.
Q) Where should I buy my LEDs from?
A) You can buy LEDs from a lot of places now for great prices. A great place I have found to buy
LEDs for low cost is http://www.besthongkong.com/. You can also get LEDs from from
Jameco or Digikey.
Q) What is the difference between wiring a LED in parallel and series?
A) Without going into a lot of detain this is the difference.
Series 
Parallel 
Tools and Skills needed:
- A Few hours
- A Soldering iron and Solder
- A few basic tools like a socket wrench and torque heads
- Basic understanding of electronics
Buying the electronics you need:
1) You are going to need 11 LEDs for a Camaro (I recommend buying more)
2) You need to pick what color LEDs you want and find a High MCD output LED in that color (look in the question and answer section
for more information).
3) Once you selected the LEDs you want you must figure out how much resistance you need in order to run each LED. Use the following
equation to find the correct ohm value:
For 1 LED per socket:
+V - (V led)
Rs = ---------------
Iled
Rs = The ohms of resistance needed (the resistance value of the resistor)
+V = Input voltage (About 13.45 volts in my car)
V led = The volts the LED is rated at (mine were 5v)
I LED = The amps the LED uses (mine was .02 or 20mA)
Example:
13.45 - 5
Rs = --------------- = 422.5 Ohms
.02
For 2 LEDs per socket wired in parallel:
+V-(V led)
Rs = ---------------
Iled + Iled
Example:
13.45 - 5
Rs = --------------- = 211.25 Ohms
(.02 +.02)
4) All you need is 1/8 watt resistors. I used 1/4 watt because that's what I had available. If they do not make a
resistor in the value you need you can put two resistors in series and add the values to get the correct resistance (can be off by up
to 15 ohms). For example I made 423 ohms of resistance by wiring a 390 ohm resistor and a 33 ohm resistor in series.
How it's done:
| 1) | Remove the 8 screws holding on the plastic dash cover | |
| 2) | Remove the 2 10mm nuts | |
| 3) | Reach your hand behind the dash and squeeze the tab on the speedometer cable to release it. | |
| 4) | For extra brightness I recommend you paint the back of the reflection plate in high gloss white. The reflection plate is that black plate that covers the gauges on the front. The back of this plate is painted a light blue. (sorry I don’t have a picture) | |
| 5) | Remove the gauge cluster (may have to loosen and lower the steering column) <--- This is what is looks like out |
|
| 6) |
|
Use 2 different color permanent markers the to label the positive and negative wires on the back of the gauge cluster (LEDs are polarity sensitive) |
| 7) |
|
Remove the bulb from the bulb sockets. Start by bending the two contacts from the bulb off the socket with a small flat head screw driver. You can use small needle noise pliers to prey the wires from the bulb off. |
| 8) |
|
Use a small piece of plastic or anything nonconductive to center the LED. |
| 9) | 
 |
- Stick the LED in the socket - Solder the negative LED to one side (the negative lead is the shorter of the two leads on most LEDs) - If using one resistor attach the positive lead of the LED to the resistor and the other end of the resistor to the other contact on the bulb socket (the contact that the negative is not hooked up to) and solder the joints. - If using 2 resistors do the same as above just wrap the resistors around the socket. <--- I had to use 2 resistors |
| 10) | Mark the positive side of the socket with a red permanent marker. | |
| 11) | Put modified bulb sockets back into the gauge cluster. Make sure that the positive side of the bulb socket is matched up with the positive wire on the gauge cluster. | |
| 12) | Put gauge cluster into car and tighten the two bottom 10 mm nuts. | |
| 13) | Test the LEDs by turning on your parking lamps. If some are not working then you probably put the bulb socket in backwards. | |
| 14) | Reassemble dash and enjoy! |
Page content last updated: January 2006