Join Date: Apr 2016
Location: Golden, Colorado
Hyperflash, but only when headlights are on.
I installed LED tail lights/brake/turn signals with resistors, and switchbacks in the front sidemarker/signals with resistors, and I am getting hyperflash and DIC warning, but only when the headlights or parking lights are on.
All signal lights each have a 6Ω 50W resistor with heatsink per bulb, so I have a total of 6 resistors installed.
I installed the tail lights and resistors first, and they worked fine with lights on or off, no hyperflash, but once I got around to doing the fronts, I started to have this problem. The DIC says it is the rear signals, but they do light up correctly, and worked fine before the front signals were done. By the way, when I have the hazard signal on, they don't hyperflash, with or without lights.
I know there are others on here that have all 6 lights converted to LED with 6 resistors, so I don't know what I am doing wrong, or where to go from here. My guess is that the 3 resistors in parallel are not the right impedance overall 1/(1/6Ω + 1/6Ω + 1/6Ω) = 2Ω, when I had just the rears, it was 3Ω (not counting the resistance of the front filament bulbs).
Anyone have suggestions? Anyone have this problem and fixed it?
I think my next thought is to measure the resistance of the OEM filament bulbs, measure the resistance of the LEDs, and get a resistor that brings these back to the same number. 6Ω might just be the "easy" number that brings it close to the correct value, but maybe not in the case when you use all 3?
One other question that I have is why everyone uses parallel resistors? When you want to increase the resistance of a load, usually you add it in series, parallel is usually used to reduce the resistance. Is this just because it is easier to do with splice taps? (Whereas series would require to actually cut the wire to add it in...)
Also, "search police" can cool your jets. I did search. All I found was people saying to use resistors, I didn't see anything with a problem like mine.
Last edited by monkeyracer; 03-20-2017 at 10:18 AM.