One of the handsets for our cordless phone (Panasonic KX-TGA230B) got left out of the patio table last night in the rain. As of mid-afternoon it’s still not responding to any of the buttons? Will it eventually dry out and work again or is it toast?
It might be salvageable. Pull the battery, open up the case and remove the circuit board. Use paper towels to sop up any obvious water, then use a hair dryer on the circuit board for several miunutes on each side. If you haven’t got a hair dryer, then just leave it open for a day or two in a warm, dry area. Inspect the board for any signs of corrosion, and if you find any, use a fine wire brush or battery contact brush to remove it. Unless you’ve got a fair bit of experience with electronics, that’s about as much as you can do. Reassemble it, reisntall the battery, and give it a try.
Remember that many phone handsets need to be resynced to the base after having the battery removed. Normally this is done by unplugging the base power supply, seating the phoen in the charging cradle and plugging the base power back in, but newer multihandset phones may not need this or may use a different procedure. Check your owner’s manual.
Remove the battery, take it apart if easily done, and rinse it well in clean tepid water, shake off the excess water and blow with “canned air” if needed, then let it sit in a warm dry place 'till completely dry. Heat ( the hair dryer) is your enemy, IMO. So’s the lint and static from toweling.
Often electronic stuff will recover with no action on your part at all.
Peace,
mangeorge
Hair dryers don’t run all that hot. Unelss you get the nozzle right up to whatever you’re drying, it’s not even hot enough to soften most plastics–if it were, it could do considerable damage to your hair. A heat gun, on the other hand, would be very bad.
My roommate once used the ol’ Windex and FreBreeze drench method of cleaning our cordless handset. We had the same thing: no button response. It dryed out after a few hours and all is well.
Some of us in the trades call a heat gun a “hair dryer”. 
Still, considering that flickster sounds to be a novice around electronics, I’d offer advice on the side of caution.
Indeed, if you’re in a hurry, use a hair dryer. But hold it far enough away that it feels quite warm, but not hot, on your hand. The only advantage of heat, though, is speed.
Tell my ex-wife (Ol’ Brillo Head) that dryers don’t get “all that hot”. 
I’d advise against using stuff like this, since you don’t know what all the components are. If you must clean contacts, PCBs oar other electronic components, it’s better to use either pure acetone, or anhydrous isopropyl alcohol. These will dry completely and leave no residue which might result in corrosion.
Kinda. But the faster you dry out the electronics, the less chance you have of damaging corrosion forming. Drying as quickly as possible is good. But your advice about watching the heat level is good.
Thanks for the response. I’m not all that much of a novice with electronics, but had no actual experience in disassembling the handset and drying one out. Packaging designers gave up on the simplicity of the screw when putting this thing together. I wasn’t sure that even once dry again if it would come back to life.
You’d be surprised where designers put screws. If the phone has a plastic window with a slip of paper under it, intended for marking the telephone number on, they might be under there. Often they’re in the battery compartment, possibly under a label. Rubber feet are another place screws often hide beneath. Sometimes, the cases simply snap together. Look for the releases inside the seam formed by the two halves–they’ll look like small notches or recesses. You can push in with a screwdriver and lever up to release the snap. Continue as needed.