Fixing GE Microwave

Last week at work, the GE microwave in the kitchen area of our offices was working  hard for us continuously during lunch time - 3 person heated their lunches,  until the 4th person put her food in. Everything looked fine, but the microwave's plate was not rotating. The microwave stopped working! She screamed for help. My office was next to the kitchen area, so I was the first to come out to take a look.

I quickly determined that it was likely due to the fact that the latch malfunctioned, it was not engaging. Upon checking on the latch, I further hypothesized that there must be a spring like mechanism that try to keep the latch in lock position.

Broken latch

test of hypothesis 

Open the door, the latch was found to be free. 

To check the\ hypothesis, Pete placed a rubber band  on the latch, and pulled downward while closing the door. The microwave worked! The hypothesis was right. So the spring mechanism must have failed.

Upon further checking on the door, I observed that the black inside cover seemed to be removable, and Pete pried it open and found the hook of a spring, which was attached to the lower latch, broke.  Bending the lower straight wire to form a hook, Pete made a temporary fix and  ordered a new spring.

In about 20 minutes, a root cause of failure was hypothesized based on observations, and was verified. Once the root cause was verified, the fix was easily made. 

Pete and I were very pleased. 

The spring mechanism that male the latch work

I made some other similar fixes based root cause analysis and applied mechanics. The most significant repair was the central AC for two story house. Others include fixing washing machine, fixing the dryer, fix AC in my van, fix AC vent for cooling at a room ...

Different problems, different root causes, the same problem solving skills.