Intermittant Electrical Problems

Whee! Intermittant electrical problems - the great joy of the electricized and datacized car. This is especialy true for the Lexus brand owners as Lexus does not cover some of these problems with its new car warranty. One problem is that sometimes - and no, I can't nail "when" down - the right front bumper sensor goes off. Real irritating. And then after a couple of days it stops and runs properly. This is the famous detector that was doing this and Lexus said that it would not be covered by warranty. However, after taking it out of the shop, it ran properly. So it has reappeared a few times, for a couple of days each time. And now I have the automatic wiper taking a swipe or two at the windshield and then stopping. This wiper problem has surfaced after driving the car over roads that have been coated with salt brine, but none is visible on the windshield. Of course the wipers don't clean the cheapo glass right anyway, but the sensor area seems to be clear. Gosh, this sure is a lovely experience owing this car! The banging jerking tranny and the grinding, jerking brakes do provide some distraction from the electrical misbehaviour, though. The car is a 2006 430 LS ultra. Any ideas on the electrical problems? This car did have to have its $7000 radar unit replaced so the cruise control would work.