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You will likely need to attempt a basic water damage repair. Here are iFixit's instructions:

Completely disassemble your device removing all cables and opening all connectors. To displace any remaining liquid around or under any components of the logic board submerge it completely in a suitably sized container filled with isopropyl alcohol. Ideally use a 90% or higher concentration available from a pharmacist or drug store. You can use distilled or deionized water as an alternative cleaning fluid, although this will take longer to dry. Avoid solvents such as ketone, acetone, or naphtha.

Use a toothbrush, small paint brush, or other soft brush to clean the logic board of any debris or deposits from the offending liquid. Use caution as you clean to avoid damaging or accidentally knocking off components of the logic board. Pay particular attention to the connectors and ends of ribbon cables to prevent corrosion of their contact surfaces.

Once you are satisfied that the logic board is clean and free of corrosion you may use a hairdryer on its cold setting and dry the logic board. Alternatively, the logic board may placed under a desk lamp to gently warm it and dry out the cleaning fluid.

When the components are dry check the cable ends and connectors again for signs of corrosion or debris.

Reassemble your device with a new battery or one that you are confident is in good working order. If your device has been submerged it is likely that you will need a new battery. Lithium and other types of rechargeable batteries do not tolerate submersion well. Again, any sign of bubbling, bulging, melting, or discoloration on the battery indicates that it is toast. Dispose of it only at a battery recycling facility.

Once you have your device assembled, the real work of evaluating the damage begins. Look for what is working and replace parts in an organized fashion, not all at once. The likely order of failure in a smaller electronic device is typically:

Battery

LCD

Logic board

From:

Electronics Water Damage