Unresolved R1+ Quits Mid-Print

I've been having some issues with my Robo3D R1+ where it will quit partway through the printing job. I've read about the thermistor potentially being an issue, but I don't think that's the case. In every failure, the extruder head will remain in its position (will not return to zero), and the temperature of both the extruder and bed are maintained. The fans also stay on, as if the print is still underway, but the motors aren't moving.

I will be trying another print soon to capture the terminal readout, but would appreciate some guidance if possible before then. Below is more details about my situation.
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General specifications:
Slicer: Cura 2.1.2 with the files included in the thread on this forum tilted "Cura 2.1 Beta"
Printing Environment: Cold garage (~17 degrees Celsius)
Plastic: Robo3D PLA
Extrusion Temp: 210
Bed Temp: 50
Fan shroud added to stock fan
Usually printing with SD card

The point of failure has always been on a wall. I've included photos below that illustrate the problem.

The first image is with the part I first wanted to print. The second image is with a different, but similar part. Between all those prints, I changed settings like print speed and lowered the cooling fan percentage.

The third image is of the first part again, but with the holes removed. The two tests in that image are of the exact same gcode, the first one printing from SD card, and the second one (more successfully) printing from USB with MatterControl. The slicer settings were:
Layer height: 0.4mm
Perimeters: 3
Top/Bottom Layers: 2
Infill: 10% Grid
Print speed: 60mm/s
Cooling fan: 0% up to 40% by layer 5

 

Is the little fan cooling the RAMPS board still running? If that turns off during print, it can cause all sorts of problems.

 

About a week ago, the RAMPS fan started to complain when being powered on after being off overnight, but the noise subsides after 20 seconds and seems to function fine. I didn't check it after the prints though. I also do not have the printer on blocks like I've seen other people do.

I just find it weird that the prints would always fail on an inner wall, and often in a similar position. And that the USB print job lasted longer than SD card print job.

I'll try another test later tonight with the same piece again. If the RAMPS fan is the cause, what kind of error message will I expect to see in the terminal?