Every so often the rear defogger switch on my '92 245 lights up on its own. I never had this happen on the '88... any ideas as to what causes this?

When this happened to my 90, I found that the wires to the tailgate had bent themselves to death inside the hinges. If the grounds break, I think the switch will light up. Especially if you push the brake pedal. You can check the condition of the wires by looking straight down into the hinge when the gate is shut.

You're probably right. I've already played with (but not replaced) the bundle at the top right of the tailgate since it seemed to be getting pulled and the center tail light kept indicating 'out' via the dash light. It's probably the ground... thanks!