This appliance is approx 1 yr old +/-. This last week I’ve noticed the referidge is not staying cold. Noticed a lot of frost built up in the freezer, used a hair dryer to unthaw it and waited a couple hours. Plugged it back in and the freezer and refer were fine for a few days. Today I noticed that the frost was back and the refer wasn’t cold again.
I’m not afraid to attempt to fix this, just would like a couple pointers to get me headed in the right direction. Please help(wife is about to explode) 
Here are your parts
http://www.appliancepartspros.com/partsearch/model.aspx?model_id=5511825
See the attachment for the tech sheet.
Sounds like a defrost problem.
First remove the evaporator cover in the freezer so you can see the coils.
Do not let them de-ice.
If they are heavily iced/frosted over you have a defrost problem.
If yes.
Manually force a defrost cycle, see the tech sheet. When the fans and compressor turn off, you are in defrost.
Now check the defrost heater to see if it is on.
Be careful you do not want to burn your fingers.
If the heater is on then the control board (Item 5 in Section 4) probably needs replacing, re: it is never getting into a defrost cycle.
If not on.
Unplug the unit.
Remove the wire for one side of the heating element (Item 10 in Section 6) from the wiring and measure it for continuity, should be 30 ohms or so.
If the heater is OK
Remove one wire to the defrost thermostat (Item 14 in Section 6) and measure it, should be 0 ohms when frozen. Note that it opens just above freezing so must be frozen to check it. This thermostat is also a feed back to the board so when it is open (unfrozen) it should be around 56,000 ohms. Also inspect it, if it is bulged at all replace it even if it measures OK.
If both the above are OK then odds are the control board is toast…
Best way to test this is a live test to see if you have 120 volts across the heater/defrost thermostat combo when in defrost.
If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
- Always remove power from the machine otherwise you could blow your meter.
- Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
- When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale’s dynamic range.
There is a good STICKY at the start of this forum about it’s use.