Last week i put in some LED license plate lights to give my truck at Lexus look. I have a 2008 truck with 2009 LED stock Tail lights. Here is that odd thing that happens. when i put the LED lights in for the license plate lights the side marker LED on my brake lights glows.. It is not as bight as if my running lights are on but you can tell the LED is getting some power. Now when i put back in the Stock 194 bulb this glowing stops.
I have LED lights in my front marker lights and there are no problems with those and I have had them in for a long time.
the only thing i can think of is that there is some power in the lines or power is back feeding through the ground some how and the stock stock bulbs soak up this power.
I do not have a Volt meeter to test my ideas.
Any ideas from you?