Help. Putting an LED in automobile

  • Thread starter **DONOTDELETE**
  • Start date
D

**DONOTDELETE**

Guest
I'd like to put a blue led bulb in the cup older area of my vehicle. And, have it run when I put the headlight switch on.

Is this possible? I think it would look fantastic since I can't see where to put my coffee when driving at night.

How could I wire this into the existing electrical system without frying the bulb.

Any help would be great.

thanks
 
LEDTronics used to make LED's for automotive use. I no longer see it on their website. Maybe one of their dealers still have some in stock. If I find one I'll post here.
 
I like the replacement bulb idea. But, I was looking for some "mild" illumination. You know, the small little light that illuminates your ashtray when you open it.

If I were to put a colored LED in the "base" of the plastic cup holding area of my vehicle it would look real neat having the cup rest in it. Imagine a bottle of water being lit up by the LED at night.

I just don't know about stepping down the amps for the bulb. I'm sure we could figure out some way to mount the bulb.

Maybe I can take the vehicle to one of those car stereo/alarm install places. I just want one little led.

Oh wait a minute....Maybe one for the cupholder in the backseat too!! Oh no. I'm getting carried away.

I LOVE LEDS!!!!!
 
Why not just tap into the cigarette lighter leads and resistor down the bulb? Also, I would use green instead of blue since it preserves night vision. I typically hang an Infinity or Photon II around my rear view mirror while driving at night in the Adirondacks. I find the green allows you to see the road better than even turquoise, so I'm sure it would be better than blue.
 
Jest for fun, and to see if I remember any of my electronics...

Nominal voltage of the car's electrical system (usually assumed to be 12v)= 13.8 v
Max = 14.8 (supposedly)
Min = 12 (technically, 10.x, but that's "near death")

Subract the voltage required to bias "on" an LED (3.6 v for white, 4.0v for blue? Ah, RS 276-316, 2600mcd --- 3.7v)

13.8 - 3.7 = 10.1v

Typical current, 20 mA
MAx current = 30 mA

Typ resistor: 10.1 v/ 20 mA = 505 Ohms

At max voltage, that would yield 22 mA
at min, would yield 16 mA -- kind a low.

Let's try the max conditions...

14.8 - 3.7 = 11.1 v / 30mA = 370 Ohms

At nominal voltage, that's 28 mA
At min, that's 22 mA

So, pick a resistor value 'tween 370 and 505 Ohms, and you should be safe. Try 470 Ohms, it's a common value. If it's too bright still, pick a slightly higher value, or consider "scattering" the light.
 

Latest posts

Top