Robert N Bonita Springs , FL May 01, 2015 Appliance: Kenmore Refrigerator 59658642891 Kenmore Refrigerator 59658642891: Freezer and refrigerator boxes not holding temperature. How to replace Refrigerator Defrost Timer. After running some tests I determined that the problem was a bad defrost timer. The timer would occasionally fail to trigger the compressor to restart at the end of the defrost cycle. Since I had the unit taken apart, I replaced the termination t-stat and the compressor start relay at the same time. Parts came quick 1.5 days, job completed and the unit is up and running. 47 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 30-60 minutes