Is there a test? Evidently I have either a short or a loose connection. The warning comes on but doesn't stay on and it only does when I am in motion. I had a friend follow me and none of the lights on the back were out or blinking. The fronts the same. Any ideas?

 

If you have a 2002-2006 truck, then it is probally the taillight strip that holds the bulbs. See this problem alot. Remove the taillight and take off strip. Inspect to see if bulbs or bulb recepticle has any burn/hot spots on it. This is a common problem.