Anyone repaired a controller that got rained on? I put new batteries in I get a beep but it won't turn on. New batteries.

I am sorry about it. It is suggested you contact the local dealer to repair.

As a last resort to really dry electronics well. Open it up as much as possible. Wrap it in a towel like a towel you dry off with after you shower (beach towel etc).

Put the electronics in an oven. Set oven on 175 deg F and dry with the door open for about 30 minutes.

Make sure to fold the towel double on the bottom. You don't want the electronics lying directly against the oven metal grating or they will get too hot. Use a thick (big) towel.

Electronics must be unenergized.

And...WD-40 stands for "Water Displacement, formula #40"you could try that.

Also, for drying out electronics, placing them in a large container of rice for several days will help get the water out. Rice is a great desiccant, and it's cheap.

Caution to those with wet electronics.

Remove power to the unit as soon as possible.  Never re-power until you have completely dried the electronics.
Electrical damage by corrosion and shorting caused by water are the main mechanisms causing damage.
So you do not want to test whether the unit is good until you have dried everything completely.{:3_60:}

Yes, make sure everything is dry before you test it out.