I'm trying to change out a stock tail light to a LED tail light.It's on my 1980 kz750 ltd.both tail lights have 3 wires and when hooked up properly the LED works great and brightens when brake is pushed but my warning light on the instrument panel is blinking telling me my tail light is not working properly.Do i need to add a resistor or something to compensate for LED's?

 

I think i found out my answer.I'll give it a try

LED tail lights / Brake / Turn signals can be done by wiring the leds directly to your wiring coming to your tail light housing. However, one think you have to understand is, most cars recognize normal bulbs only, and if you hook leds ONLY to this wiring, certian cars will give you issues, such as not working or fast turn signals (like bulb burnt out). For Turn signals you 100% need to follow below:

Solution is to use LOAD LINE RESISTORS. What a Load line resitor is it fools the car in thinking that you still have normal bulbs hooked to the car. Since your trying to used LEDs you must place these resistors to the wiring. Please look below for the wiring. These resistors can be picked uped at any hobbie store, or Radio Shack, and the internet. You need at least 20Watt Resistors in 6ohm or 3 ohm depending on if your going to wiring LEDs in the Front and Rear of your turn signal.