LEDs only bright when everything else isn't

[NinjaPwrdAccord]

Hey y'all,

I wired two LEDs from an old set of windshield washer lights to the tray below my cd player. But after I wired them in to the cigarette lighter harness, I realized that they will only turn on when the brightness knob is turned all the way down. So when I'm driving at night, and have the brightness turned all the way up so I can read my speedometer, the LEDs are completely off. What did I do wrong?

[chessboxer]

maybe, and this is just a guess, but you hooked the neg and the pos wires up backwards, but thats juts a guess, and i could be 100% wrong. im a philosophy major, not an electrician.

[Sho Nuff]

You tapped it into the cigarette lighter? Just tun another power wire from the battery instead of the cig lighter and put a switch on it or relay it to the cigarette lighter.

[NinjaPwrdAccord]

If there's already a positive wire down there, why would I want to run another?

[GrayCar]

An LED is a diode, it will only light with current flowing in one direction. Current flowing the other dirction gets blocked.

Did you hook this up in series with the cigarette lighter? Or is the ground on the chassis?

[NinjaPwrdAccord]

Originally posted by GrayCar
Did you hook this up in series with the cigarette lighter? Or is the ground on the chassis?

I spliced the LED into the red and black wires that light up the ring around the ciagrette lighter.

[Sho Nuff]

Yeah do it seprately, just run a positive fused wire by itself and not tap it into the cigarette lighter.

[NinjaPwrdAccord]

Originally posted by Sho Nuff
Yeah do it seprately, just run a positive fused wire by itself and not tap it into the cigarette lighter.

What difference will it make?