One day when at work, parked car and noticed reverse lights didn't work. Checked fuses, bulbs and switch at transmission. Found no voltage at socket connector in trunk lid. Brought to mechanic and found to be stretched wire where trunk lid wiring comes from body in trunk. Mechanic spliced in longer wire and advised how to repair if problem came back. Also said common problems with Acura and Toyota.

Don't rip up carpet or replacing switch at transmission until you check this first. Simpler and less expensive fix if it is the case.