Wipers turn on by themselves and won't turn off.
My wife's 2005 XL7 has gone nuts. While driving home from work, her front and rear wipers turned on and wouldn't turn back off. She didn't touch the wiper controls, they just come on by themselves. Also, her left turn signal light stays lit on the gauge cluster even when the turn signal isn't on. When you turn the turn signal on, it blinks as though there is a bulb out even though all bulbs are fine.
Here's the real kicker, during the day, the car starts and none of the above symptoms present themselves, if you turn it on in the evening, it does all things stated above.