Right side lights are dim

My wife's 03 Jetta right headlight and right tail light are dimmer than the left side. The brake light is ok.

I'm assuming there is a bad ground but is there a common ground? I don't have a wiring diagram that shows the location of the grounds.

Anyone have the big book that will tell where the commonality is?

Have you checked the sockets/bulbs yet? Wires may be degrading or poor connections/corrosion

not properly locked into taillight?

Check the fuses the right and left side lights run on two different circuits. Right side might have a little corrosion

Any luck on getting your problem solved?

No. Not the fuses. Haven't had the time to do more than that.