It's probably the sensor switch on the tranny. I have no backing lights unless I push the shift lever very tight towards the park position. It's hard to hold it there while turning around to see where I'm going, so if it's really dark out, I just tap the brake pedal and use the brake lights to see. I haven't had time to research this yet, what with the other problems I've been having, but I will be getting into it soon. If you find anything, please do post for us other unfortunates to take advantage of.