LED lighting on 1996 Ranger

[CaymenBlueLongRanger]

I decided to upgrade the truck to LED parking, tail, brake and signal bulbs. I got some decent looking LED 3156 and 3157 bulbs and found out it wasn't that simple!!! Either they didn't light up or they didn't get brighter with the brake or signals on. I took a bulb apart and found they were not "dual filament" - they were "dual brightness" courtesy of a resistor on the low output side - and on another set I tried just 2 different current limitting resistors - 110 ohm for high and 220 for low. Either way, power from the low back-fed out the high - whether the rear brake / tail or the front park / signal. The FIX is cutting the wire to the high intensity side (green/white or white/green on the left - didn't pay attention on the right - the opposite outer wire from the black (ground) in all cases and insert a diode rated for 20 volts or higher and 2 amps or more - (I used 50 volt 20 amp) with the cathode (stripe end) towards the bulb. No more back feeding and everything works perfectly except for the hyperflash. I put in an EP27 but there is an issue with the hazard circuit backfeeding the directionals when the key is off - and the flasher clicking with the key off. The current draw is VERY LOW so it's not s serious problem - but I am waiting for a re[placement flasher and if that doesn't fix it I have a almost perfectly foolproof solution in the wings - will post it if the fix ends up being required.

 

[89Twincharge]

Led flasher relays are a must! Also diodes on the power feeds to relay