I started converting the tail lights on my F150 to LED but have a problem. The tail lights worked fine with the oem filament type 3157 bulbs. I purchased 12-LED aftermarket 3157 bulbs for the replacement and installed those bulbs. Both tail light light up when the brake is pressed. When the lights are turned on, only one bulb lights up and it only lights up when the other tail light bulb is placed in the opposite socket. The bulb that lights up when the lights are turned on will also work when the turn lever is used but the flash sequence is too fast. If the turn lever is switched to the side where the LED does not light up, the license plate light will flash on and off as well as the odometer display and dash lights. I have not replaced the front turn signal bulbs with led. Do all the bulbs in the circuit need to be led to work or do I have a compatibility issue?

 

wow

 

The info I've found recommends the installation of load resistors at each LED bulb to present a proper load to the various circuits in order to make them work correctly, particularly the flasher system.

Take a look at this site for some of that info:

http://www.superbrightleds.com/carbulb-notes.htm


Check to see that the LED lamps you have purchased are NOT polarity sensitive. A proper design should not be, but you never know.

I considered LED lamps in my vehicles, but aside from long life I see no advantage to changing over to them. A good set of standard long-life bulbs is cheaper in the long run and does not present any operating issues.

 

Kattumaram thanks for the info and Superbrights website. The LED bulbs that I bought are polarity sensitive. In the very center of the bulb between the LEDs, there is a small + and -. When installing the direct plug-in bulbs I found that if reversed a light in the socket, the one light that would light up would not light. Being polarity sensitive seems to eliminate the use of resister wired across the positive and negitive leads.

The Superbrights website indicates that changing the flasher unit to an LED compatible one might fix the problem but since the flash rate or not flashing is not the only problem, I doubt that it is the solution.

Other interesting complications (I left them in for a day) when I press on the brake, the overhead display and the odometer display both go blank until the brake is released.
Applications:
Simple replacement of LED bulbs for Tail lights, Turn signal light, Corner light, Stop light, Brake light, Parking light, Side marker and Backup lights.
Easy to install, plug & light!
Feature:
Long life, energy saving notably and super bright! High quality guaranteed. We will have tested the items before shipping. No defective bulbs will be received.
Just find the right bulb for your vehicle in our shop!

Model:MLBT3157-24/2(W/Y/R)
Specification:12V 24LEDs Per Bulb
Pack Size: 24LEDs 2 bulbs
Size: 41 mm X 25 mm
LED Color: Red

 

I have leds on my motorcycles , you have to change the flashers , f using resistors. look for the trailer flashers they run about 7 dollars or so. superleds or some other one I use on ebay is good and they seem to fit fine. Don't use resistors thats the same as having the oem, but more money.