Ready to Upgrade Switches to LED Bulbs?
Dashboard lamp DIY LED conversion
“After making the first one, I got a lot faster – I can make one every 2-3 minutes now. So I started an assembly line, and replaced all the lamps in all the switches along the dash. No more fumbling for my TRACS button, or for the fog lights because the stupid bulbs have burnt out again… And now the red is much better on my night vision during Rallies.”
Dashboard lamp DIY LED conversion. Very detailed with pictures.
Dashboard Switch Lights LED Conversion DIY…
Upgrade Switches to LED Bulbs
DWeisbrod » I figured out the polarity by using my multimeter. When measuring the voltage off of the switch housing, if I have the leads reversed on my multimeter, it shows a negative sign. So that was easy enough. Then you just need to take into account the fact that you are turning the lamp housing clockwise to tighten it, and the line it up right. I did it wrong once or twice, and it was easy to just pull the housing back out and then rotating it 180 degrees. If the LED doesn’t light up and you know you’ve got it all tight, then you’ve got it wrong! 
tblo760 » To check polarity of a 2.7 volt led,set your multimeter to continuity,this will supply approx 3 volts to the led which is a diode and will only pass current one way.Also new leds will allways have the positive wire longer than the negative one.If you dont have a multimeter two 1.5v batteries will do,or connect a 480 ohm resistor in series to your 12v supply.Connecting the led the wrong way will not harm it,it just will not light up.Also for the older type switches with the removable bulb you can connect the resistor into the supply wire.You can allways connect leds in series without a resistor,eg; five 2,7v leds in series would light up ok from you car’s supply.LEDs can last for years and if you don’t over load them,they’ll last forever.Good luck,Terry.
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Last Updated on April 25, 2021
