OK, just swapped out the ICU and that fixed everything that was going wrong on the dash on my car, so I would highly recommend that you look into this as a likely cause as well.

Note too, this was a bit of a pain in the ass to do... took me about 1 1/2hrs. Fair amount of crap to disconnect/remove to get the ICU out. I ended up removing the driver's seat so I could really get in under the dash, and that made it a lot easier.