Here's how to change the LED colors and/or reduce the brightness of the LEDs in an Escort or Beltronics Smartcord.
The tools you'll need include a soldering iron, some solder, a desoldering tool (wick or a solder sucker), replacement 5mm LEDs if you're changing them, and a 2.2k to 4.7k 1/8 watt resistor to reduce the LED brightness.
The pictures show a hardwire Smartcord, but the procedure is the same for the lighter plug version.
1. Remove the screw(s) from the display housing. 1 screw for hardwire, 2 for lighter. If you're taking the lighter plug apart, be careful not to lose the plunger or spring. You'll need to peel the decal off, which is easier once you get it half off when opening the housing.
2. Carefully remove the circuit board from the housing. It might be stuck in there a bit, so you might have to gently pry it out.
Once you get it apart, and remove the board, it'll look like this:
To change the LED color, you'll have to unsolder the old LED and replace it with one of a different color. On mine, I changed the alert color to yellow and the power to red (I reused the original red alert LED for the power LED). Make sure to install the new LEDs with the correct polarity (cathode or - lead, which is the shorter lead, is away from the mute button). The LED itself has a flat spot on the flange on that side as well.
If the LEDs are too bright for your taste, replace the 470 ohm resistor R4 with a higher value. I installed a 4.7K in mine which dims the LEDs nicely. If you don't want them that dim, you can use a 1K or 2.2K.
Put the thing back together (don't forget the spring and plunger on the lighter plug version), put the decal back on and you're done!