Working on fridge for family member. Fridge stopped working couple weeks ago and I was called to check it out. Then received call that it started back up again. Next day received call that it stopped again. Went to check it and when I opened door unit kicked on. Suspected defrost timer but couldn't figure out how to get to it. Left to do online research. In meantime, owner discovered that bumping fridge whenever it stopped working caused restart. Confirmed timer suspicion (so I thought). Purchased new defrost timer locally and installed after I discovered panel on controls that needed to be removed to get to timer. Installed new timer and everything worked for about 1 week and then same thing happened again. Could this be a faulty cold control instead of defrost timer or might I have gotten a defective new timer? Presently have bypassed the timer completely with jumper while I try to figure things out. Guess this may reveal if there is a bad cold control. Any help would be appreciated.

Is the defrost timer supposed to get warm when it runs? I hooked the new one up directly to power and although it worked correctly, it got very warm, almost hot.