Paging a Refrigerator and/or Condensation expert

Trying to figure out if I have a problem (I think so) and what could be causing it (??).  We have a nice, built-in Kitchen-Aid refrigerator that's about 3.5 years old.  It may have been doing this for a long time, but I've noticed that we have various amounts of condensation on the bottom under the freezer side.  

The hinge pivot on that side has rusted badly one time while under warranty and they replaced the parts they could and it restored the door's closing ability.    It's happened again and is out of warranty so I tackled it.   it was, again, rusty, so I cleaned everything up and greased it so it's better but I also saw that there is a lot of condensation on the bottom.   Sometimes the bottom of the door itself has it, and sometimes not.

The seal seems to be fine. I don't feel any cold air coming out from around it.

Here is a pic of the bottom. the hose in front is for the ice maker/water dispenser. You can see a drop on the line, but the line is not leaking.

You can also see some rust/corrosion on the ground wire to the side. The water you can see goes back about as far as I can reach.

We live in southern california near the coast, so it's not typically humid but can get overcast.  I haven't tracked this long enough to notice any trends.

Any ideas???

We have a 15-year-old KitchenAid counter depth fridge that started peeing about 5-6 years ago.  Bottom mount freezer.

In our case it was the (IIRC) the freezer defrost drain. It got enough dust and crumbs in it that it started freezing solid, then it would leak.

I was able to fix it myself by taking the freezer section out to find it, then defrosting and cleaning the collector tube. I can't remember if there was a revised part to help stop that from happening, or not.

Google the model number and "leaking" or "water under" and I bet you get some leads on the issue.  Good luck.

appreciate it. I'd read about drain lines, and I will look for one to see if that could be an issue.   I'm not holding my breath but maybe it is?   It just looks like condensation on the bottom that sometimes is on the bottom of the door as well.

Yeah, ditto to looking at the drain. I was able to get mine cleared using some hot water after chipping the ice out. There is a heater on the condenser to de-thaw it, so I wrapped some heavy gauge wire around the heater and ran it down through the drain to help keep it from freezing over again. 

Like you said, you have lower humidity than me (NC), so it might not be that, but it should be very easy to at least check 

In reply to jfryjfry :

Also check and see if there is a heat element that evaporates the condensation out of the pan. If so, that could have failed.

Ok can I pile on since this seems to have a solution for the first problem? 

I have a Whirlpool WRF 535SWH204 that if you set it to 4 it cools to 41 deg. If you set it to 5 it goes to 28. I have read it may have a bad thermostat, not sure if that's true or not. I also can't seem to find the part on the normal online sites. 

jdryjfry, I'm happy to delete and start a new thread if your problem isn't answered yet.