Did some research on the Internet and observed the fridge. Symptoms pointed to a bad compressor start relay. Got a new one from from AppliancePartsPros. When I removed the old one and shook it, I could hear loose parts inside, which matched the online troubleshooting info. With the new relay, fridge appears to operate normally. The old relay cover was broken in pieces, which I didn't notice previously, so I'll have to order one later on. Very satisfied with price and service from AppliancePartsPros.