Another experiment to use LEDs for brake lights of Daihatsu Move

I have tried to use high power LEDs for brake lights as an experiment for a

Daihatsu Move. I used the LED array shown below.

 

This array is originally designed and made to use for backlights application

such as LCDs or room lights. It has a red, two greens and a blue LED chips

inside with a lens. My application is for brake lights and I only need to use a

red chip inside.

 

The array was consisting of 5 units but for tail lights I dare used only 4 with an

additional silicon diode aiming to prevent to stress the top LED when only

tail light switch was on and also thought that the plus one LED would be better

to be recognized when braked. I also needed to compensate the voltage

change between 11-14.5V with the brightness ratio more than 3. To meet

this condition, I made a circuit below. As I measured the actual ratio using a

light meter, it was between 3.3 -4 and it did meet the specification.

 

The original bulb was attached at the bottom side of the brake lamp housing

and I removed it and inserted the LED array with a handmade aluminum plate.

The electrical connections were all done just by the soldering since the life of

the LEDs were expected long enough.

 

Tail lights on.

 

Brake lights on

 

The experiment was over just before the Shaken or the inspection by the

government. The result was all passed including other items. So my

modification was no problem with it and I can say my experiment was

successful.