ALL LEDs (Light Emitting Diodes) are polarity sensitive, as in fact are all diodes - and Suzuki tail lights work just like any other vehicle - a +12V feed from the switch to the light and the other side grounded - it is the headlights that are wired differently (switched ground).
I knew about the head lights, but I made an assumption that the entire wiring system followed with this
same logic, which is in fact according to electrical theory correct, electricity in a DC circuit flows from Neg
to Pos, not the other way, this you can verify with a Diode, because it is in effect a 1 way valve, only allowing
current to flow in one direction.
I have come across some LED lighting assemblies that were indifferent in their wiring, there is some built in
circuitry to allow them to be wired either way and be more user friendly, I bet they had too many returns
with people saying these stupid lights don't work
To fix the problem, verify the polarity of the wires, and follow the directions on the package (if included)
and you should have no trouble. If there are no directions then use a 12V power source like your battery
and touch the wires to the terminals, you will quickly figure out if the light is polarity sensitive or not, then
hook up the wires to the appropriate ones at the back of the truck, and for turn signals, you need to use
a heavy duty flasher, these are the ones that do not require a load to work properly, and because LEDs
have nearly a zero load the regular flasher will do nothing, the lights should just stay on, no flash
Wild