VW Passat corroded wires

We have a 2006 Passat, 30K miles, live in northeast on a Great Lake. We bought it used in 5/07 with 11K miles on it. The other day, a whole mess of warning lights came on, and the car went into “limp mode.” The dealership diagnosed corroded wires where they connect to the throttle valve controller. We usually keep our cars for years, and we’ve never had corroded wires before. Is this a typical problem of VW’s? The service mgr said he’d seen about 6 come in in the last year, but I don’t know if that’s a lot or a few compared to other brands. We’re getting ready to shop for cars again, and we’d consider a new Jetta, but not if it can’t go out in the rain. Also, if the wires corroded once, what will keep them from corroding again? Should we expect this to keep happening? Thanks in advance.

Has anyone checked the car's computer for error codes?  This should be one of the first things done.

I think that’s how they figured out it was the throttle controller wires that were the problem. They fixed the wires, and everything seems copacetic. I asked why the wires corroded, and they said something about “water gets in there.” Is this common in VWs? Is it a VW design flaw, and, if so, has it been corrected since? Or was it just some fluky thing that happens sometimes?