Hi Andy, My name is Mike and it is my pleasure to assist you. Yes when the circuit board gets wet and will not respond you will have to replace the movement which is almost the cost of a watch depending on which model you have they make about a dozen different types rangeing from $125.00 to $1325.00 for the smart butterfly oceanus. You can contact Casio in the UK direct with the information below and you can determine if you would like to repair your watch. Thanks Mike
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