You will have cut the cable while using the trimmer - easily done.
Cases are usually held together with Torx (security) screws to prevent casual dismantling. My guess is that you used a crosspoint screwdriver and failed to loosen any screws.
You can buy or borrow a Torx driver set or you can fit a two pin cable joiner - very cheap from Amazon or a hobby electronics shop.
Good Luck...
September 2015
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