2000 Mercury Sable Wagon 3.0L automatic. When I put it in reverse, the backup lights come on but just barely. Both bulbs come on but they do not put out any measurable light. Any ideas?
Try taking out the bulbs and cleaning the sockets with a good cantact cleaner. Problably have a bad ground which will cause the cause for dim lights.
You can probably do te same will somethig lightly abrasive both on the socket and the metal side of the bulb.
I would suspect the switch in the transmission is causing that but it also could be a bad power connection to it.