Hello

a friend of mire dropped the key in the lake and found it 24 hours later

I opened it and soaked in WD40 and let it dry
For the moment it works well but I was wondering if later it will start the corrosion

Does anyone have similar experience?

Thanks

Yes I have done that before have you tried putting it in some rice to draw the moisture out then give it dry with a hair dryer might work failing that.it is possible to code a key with only the vin number 

Suggest giving it another wash out in pure alcohol after removing battery, then gently dry.

I washed it with WD40 after removal of the battery and plastics, Dried out and since then is working great