I have a 05 500ES 4X4. Recently it doesn't want to down shift using the ES button. It almost sounds like it is a weak soleniod. I can rock it back and forth several times and get it to work but when i am riding and slow down is when it usally happens which seems to be getting worse. I looked in the manual and of course it says carry it to the Dealer but I would rather buy the Overhaul Manual and work on it myself. Any information is appreciated.