Instructables
Picture of License Plate LEDs
Have a few LEDs and resistors laying around. Why not convert your license plate lights to LEDs.
 
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Step 1: Gather the Tools & Parts

Picture of Gather the Tools & Parts
Parts:
White 5mm LEDs (you determine how many to use)
¼ resistors (value determined by how many LEDs you use)
Proto Board

Tools:
Diagonal Cutters
Solder & Soldering Iron

Step 2: Planning...

First you need to determine how many LEDs your going to use. Then use one of the many online led calculators to determine resistor value. Most of the calculators will even make a diagram as how to wire your LEDs.

Below is a link to one I often use.
http://led.linear1.org/led.wiz


Step 3: Putting it together

Picture of Putting it together
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I only used three LEDs to replace each bulb. The proto board is cut roughly the same size as the bulb that’s being replaced. They are wired in series. I placed the LEDs and resistor on the proto board as to how they would be connected. I then twisted the connections that are to be soldered.  Then I tested with a small 12 volt battery I had. Now that I know they work it’s time to solder. 

Step 4: Test & Install...

Picture of Test & Install...
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Now just clip the twisted ends you soldered and test again. The positive and negative leads that extend from the end are folded over so they fit nice and snug into the plug.
supak11113 days ago

Cool project, no more getting pulled over for burned out plate light.

Have you seen the James Bond license plate hide gadget? It hides your plate with switch and remote. Here check it out ★ http://007Plate.com


I stumbled on this little instructable and thought you may be interested (for the front of your car) in a stripboard layout for a knight rider LED scanner HERE
purpulhaze (author)  Insonicbloom2 years ago
Kewl! I've recently graduated to etching my own PCBs but I may use the circuit...
luka13242 years ago
where did u buyed that protoboard and that tool that helps u hold board while u soldering...btw very helpful instructable...did the same thing to my golf mk1 78'...thank you ;)
purpulhaze (author)  luka13242 years ago
Can't remember exactly because I've had it for years. If I had to guess I would say Radio Shack.
throw a couple IR LED's in and license plates are invisible to traffic cams ;)
Nah, that would just provide better light for the camera....unless they were highly powerful like an IR Cree led
IR's do blind alot of cameras when the main beam is pointed directly at them. which wouldnt be hard to do with this project :)
KT Gadget2 years ago
Be careful with the voltage though, the alternator voltage can range up and down depending on the RPM of the engine (you can see this if you rev the engine and pay attention to the dash lights, they will get slightly brighter). Had 2 LED bulbs burn out due to the voltage change and the high current going through them (had no load to help with it :( )

A voltage regulator can solve this by dropping it to a steady, lower voltage and then use a resistor for each LED (maybe a couple of capacitors to smooth out any other voltage variation).

Other than that, great replacement that will last a while! Been wanting to replace all the lights in mines with LEDs, just have to find powerful ones for the headlights haha
veryken2 years ago
I think this is awesome. LEDs are the future. I have some designs and fixes involving LEDs that I've been putting off, so seeing this project is very inspiring. The link to the online calculator is also helpful.