DIY LED tail lights

[Memorytwo]

i know you need to use at least 1 resistor because its not all Volts, it has to do with either the watts or amps, i dont remember. the led's cant really handle the something of the feed so you need a resistor to "clean it up."

[captainslug]

Originally Posted by Christ

So basically, you'd have to ensure a stable 12v signal to the input in order to run enough LED's to not use resistors at all...

Correct.
If you had a perfectly stable 13.2 volt source you could string six 2.2 volt LED in series with no resistor at all.
The fewer LEDs you have in series and the more resistors you add the wider the input voltage the array can handle without overvolting the LEDs. But you end up consuming more watts with resistors.
4 LEDs in series with one resistor for them will generally offer the best balance between the two.

[Christ]

I smell a dirty word... compromise. blech.

[Memorytwo]

4 leds and 1 resistor, i know is because its specifically for a car i believe.
parallel sets of 4 leds is roughly at 12v per set. but i think the resistor is still required because the line voltage fluctuates between 12ish to 14ish.
dont quote me on this though.

[gascort]

I wouldn't waste time with the turn signals; keep them incandescent (just remove one wire from the bulb and use it for your led parking lights. - keep the old bulb in place and just power the high filament)
Unless you spend a huge amount of time with your turn signals on. Less cost, less hassle, less risk of not working and losing hazards as well, and no flasher change to worry about.

[Christ]

Bah, that's too easy. :P

[getnpsi]

There are frenched style tail light kits for the jeep TJ/CJ wranglers that use what appear to be the same lights used on big rig tractor trailers. They are dual intensity and can be seen forever. Not so DIY but its a clean install.

[Memorytwo]

but i have a ZJ, a 1994 Grand Cherokee. the "mods" for tail lights are slim. Just Nasty looking Altezzas.

[NeilBlanchard]

Hi,

I'm a little concerned with the optics of doing this: LED's have such a narrow beam, that getting them actually reflecting and (highly) visible from all angles. Some of the LED replacement bulbs have a center "hot spot" that shines straight back, and they have some around the rim to bounce off of the reflector, so you can see it from the sides, etc. Has anybody tried these?

7443 LED bulb Specifications

3156 and 3157 LED bulb Specifications

As opposed to these:
7443 LED bulb Specifications

[Memorytwo]

if youre gonna make your own panel of LEDs to put into the taillight, like i eventually will, they sell "flat top" leds that have a wider viewing angle.