The indoor air handler runs, but my Trane XE1200 compressor does not start. It tries to start, but buzzes for about 1 second and quits, and then retries about once per minute.

This happened for up to one day before I realized and shut it down. Could something else have been damaged by letting it go for a day?

Luckily the weather turned cool this week, because I'm in no position to buy a new compressor. Can you give me some tips on what to check with a meter? I know how to check the capacitance of the capacitor, but what else? In what order should I check what? Can you point me to a mechanical diagram (not a schematic) of this or a similar compressor? When I know the real problem, I'll be OK with hiring a professional because I'll understand if he's honest and I'll know what my money is going for. Thanks.