In this video I fix a non-functioning trackpad in a mid-2012 Macbook Pro by replacing a bulging battery that had been applying force to the underside of the trackpad.
A1278 Replacement Battery: https://amzlink.to/az0rVw2z23lOO (Amazon affiliate)
A1278 Replacement Battery: http://ebay.us/KBsm3Q (eBay Affiliate)
Apsung 110 in 1 Precision Screwdriver Set (Amazon Affiliate)
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