Hi, this one is a problem lol.
The sand has most likely gotten into the mechanical workings which are extremely fragile and tiny.In this case if you don't have camera repair experience its really best to let a shop do this for you. Best Buy and Sear both make these repair but they send it out to a shop, it can take up to two weeks for this service, but they are fair priced and honest, also they do excellent work!
Or if you have a local camera repair shop near you they can also do this. But for this fix, the entire camera needs to be dismantled and there are a lot of little parts likely to spring out of place when you open the case, not mention very delicate ribbon cables that most of the time break any way and they will be replaced by the shop.
Not a do it yourself repair Im afraid.
In any case, I will stick with you until this is complete.
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