A burned-out incandescent bulb is not only a nuisance, it is a safety hazard which can contribute to an
collision (which will be your fault) and an equipment failure that can get you pulled over by he police, and possibly ticketed for "faulty equipment" if the LEO wants to "bust your balls". LEDs have a lifespan of over 40 years of continuous use; and as a signal light, will be working long after most all of us have shuffled off this mortal coil.
Unfortunately, you cannot just replace your tungsten filament light bulbs with LED lamps that just happen to fit in the socket. Most Web sites that sell "LED replacements" for vehicle signal lamps (with notable exceptions) do not mention this fact. The flasher circuitry in almost every vehicle (still) on the road that isn't an antique and doesn't already use LED lamps, has a circuit that detects a burned-out bulb, and this will cause your turn signal to flash twice as fast as normal, and/or displays some sort of indication that alerts you to check your lights. In addition, the LED may not illuminate at all.
Many sellers that advocate switching from bulbs to LEDs cite "energy savings", since LEDs consume a fraction of what filament bulbs would. However, if you must add resistors in the circuit to "fool" the flasher circuitry into thinking a regular bulb is installed, you lose the "energy savings", which is a pittance anyway, and all you'll gain is that you'll never have to replace a bulb.
If you want to replace a filament bulb with an LED bulb, you'll need to simulate the current draw that a filament bulb presents to the flasher. You will need one resistor for each FILAMENT – the turn signal / brake bulbs have TWO filaments, and so you'll need one set for EVERY two-filament bulb, and another set for every TWO backup lights and every TWO side-marker lights (which have single filaments) that you want to replace with LEDs. An easy way to determine how many
these sets you need, is to remove all the bulbs you want to replace, and count the contacts at the base of the bulbs. In case of bayonet bulbs, you will need one set for a bulb with 3 wires, and one set for every TWO bulbs that have 2-wire contacts.
I found a distributor that sold a flasher unit for $11.99 that claimed to eliminate the need for the installation of load resistors, so I purchased it. After installing it, not only did it NOT work, but it somehow caused the power to my cigarette lighter socket (where I have connections for my GPS and
Dashboard Cameras) to flash on and off like a signal light. I called the manufacturer with my vehicle data, and they told me to remove the center pin on the flasher. After I reluctantly did that, it wouldn't work at all (well, duhhh!).
After weighing my other options, and assessing all the work that would be required to convert my bulbs to LEDs, I decided that it wasn't worth the trouble. However, when I replaced the
worn-out and cracked front signal lamp housings, I converted those push-in bulb sockets to the same ones that are used for the rear bulbs. I carry 2 spare bulbs in my toolkit, which will now replace either the rear or front signal lamps. I also removed the rusty factory Torx™-type galvanized screws on all the signal lamp lenses, and replaced them with #8 x 3/4" Stainless Steel Phillips-head sheet metal screws; this way I wouldn't have to go hunting for a
TorxTM Driver if I ever needed to replace a bulb... I could just use the Phillips driver on my
Leatherman WingmanTM Multi-Tool.
diagram shows what you need to do to convert Incandescent bulbs to LEDs
in a Jeep or other vehicle. You will need to use the (above) specified
for each turn / signal lamp. For a Jeep Wrangler (and most other
vehicles) you will need 4 sets. For side marker lights, and / or backup
lights, you can leave the incandescent bulb in place, or convert them to
Depending upon what flasher module you have, you may be able
to use 25 Ohm, 10 Watt resistors for the side marker and backup lamps. You can get
these resistors at Radio Shack.
WARNING: DO NOT
SUBSTITUTE WITH LOWER WATTAGE RESISTORS. If you use low wattage
resistors, you WILL end up with an electrical fire (the resistor will
heat up, and the fuse will NOT blow).