Where is the defrost timer!? Please Help

Hello friend, I am no expert in fridge what so ever. In question is jenn-air frost free model JRSI223.
It works, it does not cool. From the web search I did till now…fen works…light turns off when closing the door…engine runs, I can hear it, but no longer can I hear that noise every now and then when soothing turns on…you know what I mean… In the freezer at the bottom part, back wall I see some fine ice shaving typo of thing accumulated…I wiped it off… a bit of liking from that part as well… I assume that my ten year old daughter or I for that mater have left the freezer door open with a first ice cream of the season… might be two tree days that started… I vacuumed the back of the fridge where the condenser is… also just unplugged the fridge from the wall…in freezer to mention there is some cold air coming, so I think… by the research, I might be wrong, but if I reset that defrost timer I might be ok and fright might be cooling again…problem is I can not find defrost timer… I unscrew couple of screws from the freezer wall, but managed only to kind of peek into the upper part, as I do not know how to move the inner wall cover, and I scared not to brake something if I jerk it to hard…Can someone tell me where is this defrost timer…and what to do when I find it…. Thanks…

It’s part 20 on this diagram. It’s under it at the front behind the kick panel. http://www.appliancepartspros.com/sect/0/9/z/09zi8gjjjf.gif

See how to check your defrost heater, defrost thermostat and timer here. Refrigerator Repair Guide: How To Fix a Refrigerator - ACME HOW TO.com