Ok. Today I learned some important information for a VERY expensive price. For quite some time now, my 3rd brake light has chosen to stay on all the time- even when the car is off. So, I took it to the local Ford dealer and they thought it was the wiring. They replaced my tow/brake wiring and gave it back. Later that night, someone felt obligated to tell me "hey, your light is still on, you know." what the F%&@. So i took it back the next day, and they went back to work. They took my WHOLE interior apart and checked all the wiring and relays: under/inside the dash, inside the doors, rear quarters, liftgate, inside the taillights, trailer harness, etc etc- EVERYTHING. Then they decided to check what I had for bulbs in my clear tails. I use a set of 3157 Red LED bulbs for my brake lights. They replaced these with regular 3157 bulbs for experimental purposes and everything was back to normal- no more naughty 3rd brake light. The cause of this, they said, was that the LED bulbs had an improper resistance level in comparison to the stock incandescent 3157 bulb. The way the 3rd brake light works, is by a resistance module. when the resistance of the brake bulbs lessen (i.e. when you hit the brakes and the bulbs light up passing current through them) the module tells the 3rd brake light to come on. Since the LED bulbs had a lower resistance than stock, the module thought the brake lights were on all the time, thus keeping my 3rd brake light on all the time.
So, now that the problem has been discovered, and I paid my Ford dealer some hefty cash just for a lesson in bulb resistance and no fix, I need to find a solution. My first thing was, "ok- we'll just splice some resistors into the power leads to the bulbs." that won't work, because now you're limiting the power that the brake bulbs themselves see, and they won't light up properly.
SO I NEED HELP! hehe. Has anyone else had this problem using 3157 LED bulbs for your brake lights? If yes, what did you do to fix it? If no, what brand LED bulbs were you using?
THANKS!
Eric
So, now that the problem has been discovered, and I paid my Ford dealer some hefty cash just for a lesson in bulb resistance and no fix, I need to find a solution. My first thing was, "ok- we'll just splice some resistors into the power leads to the bulbs." that won't work, because now you're limiting the power that the brake bulbs themselves see, and they won't light up properly.
SO I NEED HELP! hehe. Has anyone else had this problem using 3157 LED bulbs for your brake lights? If yes, what did you do to fix it? If no, what brand LED bulbs were you using?
THANKS!
Eric