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Discussion Starter · #1 ·
Want to change the color of your start button? Here's how to do it, and believe me, it's easy.

Parts Needed:
-Clear (insert color of your choice) LED (10 candela)
-Resistor (this depends on the LED)
-Super Glue
-Solder
-Heat Shrink tubing (big enough to slide over the resistor)

Process:
Pull the panel off that includes the start button and lighting switches. This is done by removing the two phillips screws at the bottom of the panel inside the coin tray, then pull straight down to remove the panel. Disconnect all the electrical plugs and take the panel to your workbench, kitchen table, bathtub, wherever you're comfortable.

Start button assembly removal:
The start button assembly is composed of three major parts.
The Button
The Switch
The Harness

Remove the harness by pulling it straight off the assembly.
Remove the switch (the square block that the harness plugged into) by locating the recessed slot on the side, depressing the tab with a small screwdriver, and pulling it straight off the start button.
Remove the button from the panel by unscrewing the thumb nut down the threaded body of the button. There are some aluminum rings that hold the button in place, just set them aside until you reassemble.

Opening the start button:
The button itself comes apart at the very bottom. You'll see the seam and tabs. It will probably break in your attempt to open it, mine did. Be aware of the two little springs inside.

How to prep the bulb base. Pull the bulb out. Use a small pair of needle nose pliers to pull the metal contacts out. The bulb contacts should have slip on connectors connecting them to the base. Note which terminal the small spring contact is connected to. This is the POSITIVE terminal. Once those are off, snap, cut, or chew off the plastic holder for the old bulb, so you have easy access to the slip on terminals.

Now it's time to solder. Cut the leads on the LED so that the bulb will fit well into the start button and won't interfere with the button's operation. Next, take the round metal (NEGATIVE) contact and cut each side of the partial circle so you have a straight piece coming straight off the slip on connector. With the other connector (POSITIVE), use your needle nose to straighten the metal coming off the connector. Solder these onto the LED leads. The anode of the LED goes to the POSITIVE connector, the cathode of the LED goes to the NEGATIVE connector. Slide the connectors back into place on the base. Polarity is very important. LEDs are diodes and only allow current to flow in one direction. Slide the bulb and the base back into the start button (don't forget the two little springs). Check the operation of the start button. Make sure nothing is rubbing or interfering with its operation. It should feel stock with a full range of motion. If it works correctly, resecure the base (the bulb base, not the switch) to the start button using super glue if necessary.

Cut the red wire in the harness and solder the resistor in line with the wire. Then protect the connection with heat shrink. It's easier to do if you pull the pin on the end of the red wire out of the white connector at the end of the harness (the end that connects to the car). It's tricky but worth it.

Reassemble the start button assembly.

You're done!
 

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Discussion Starter · #3 ·

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Great info, but part #'s and source for the specific LED and resistor's you prefer would help (sorry, I'm electrically challenged, and would not even attempt this without it spelled out for me like I'm 5 :D).
 

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Great attention to detail!

Thanks for taking the time to post all your hard-won expertise for these two mods.
 

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Discussion Starter · #7 ·
I assume you're using the resistor mainly for current limiting. Or are you also dropping the voltage down to 5V?
Is that a loaded question? :evil: I'll be the first to tell you that I am not an expert on LEDs. When I purchased my LEDs, I was fortunate to find the required resistor size for a 12vdc application listed right on the package.
 

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Hi I'm Rick. This is my first post, but I've been lurking for a while. I couldn't resist answering this post because my lamp in the start button is beginning to blink and go off occasionally. So, I'm going to replace it with an LED. I'm a CprE/EE. Of course, it's been 17 years since basic circuits.

R = (VS - VL) / I
VS = supply voltage
VL = LED voltage (usually 4V for blue and white LEDs)
I = LED current (e.g. 30mA), this must be less than the maximum permitted

Super Bright Blue LED at mouser.com
Electronic Components & Supplies

It's 4.5v at 30mA. Pretty standard LED.

So, it's (12 - 4.5) / 0.03 = 250 ohms.
I would suggest a 1 watt resistor just to be safe. The power from a car electrical system is not stable.
Most LED's will run on 12V directly. So, no voltage divider is needed.
 

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Finished product

Here's my new start light. I didn't order the LED from mouser. I went to my local Fry's and picked up a super bright blue LED. 3.8Vf 20mA. It's viewing angle is only 16 degrees. So, as you can see it creates a hot spot in the middle of the button. I had a white, red and green LED laying around and tried them all. They were not nearly as bright, but they didn't create a spot in the middle. But regardless, my daughter and I both voted for the pretty blue candy-like button...

I had a 390ohm 1/2 watt resistor laying around so I used that. That calculates at 21mA which is close enough. I measured exactly 20mA with my meter.

I attached a picture of the two parts soldered on. I had trouble taking a picture with my digital camera so it really doesn't do it justice. I think if I do this again, I would wait for a brighter and wider angle LED. But, it's a rainy weekend and I got bored. If it dries up I'll go racing in the morning at Driveway Austin.
 

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