If pressing on them makes them work, it is most likely a cold solder joint. Taking the 002 apart to access the PCB and reflow solder joints shouldn't require a service manual. Not much more involved that swapping a power harness....just take your time, use a clean iron in the 25 watt range(leave that 100 watt Weller gun in the drawer) and use high-quality solder to reflow the joints(and a magnifier for those old eyeballs........like mine
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