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Originally Posted by skip_168
Well, unfortunatly It looks like you allready have alot of corrosion on the top metal lay of your board..(it looks like green fuzz or powder on the exposed terminals..) this corrosion eats the top copper layer which is about .0014 inches thick, and eats away the FR4 & the prepreg in the laminate..
here is the kicker:
These boards are all low voltage operating systems, i.e. the boards run at 1.8,3.3, or at the most 5 volts, some of the relays run at 12V... this is well under the voltage neccary to use water as a conductor..(I think its around 20V or so.. salt water is less)... so this board apears to have been getting moisture in it for some time, and the corrosion just now interupted the logical signal path..
But hey, I always dry them out as a first attempt... my daughter runs her cell phone through the wash every month or so...
Dry it out as best you can, use some denatured alcohol as a solvent, & put it in the oven at a low temp.. 125deg F should be safe, but watch the plastic parts carfully.. if they start to deform then you are toast..(pardon the pun)..
I always use a vacuum chamber, but not everyone has access to an electronics lab... also, use some ESD(electrostatic Discharge) protection.. you could fry the board just by touching any of the exposed leads...
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Do what is refered to by some as a Cool Down Bake, Let your oven heat up to about 125 degrees, then once your oven is up to that temp turn the oven off and quickly and safely place your wet item in the oven and leave it there till the oven is cooled down to the touch. That's the method the we use at the shop when we customize or refinish wheels and have to dry the paint on center-caps.