Homing error X

I am having a problem with calibration in the XY direction.Starting from powered-off state, I turn on the printer, and it tells me I need to complete a "Calibration & Tests" before I do any prints (this is expected due to prior calibration fails). I acknowledge and then go to Control --> Calibration & Tests --> 2 XY Axis Test. It does a Z-axis calibration, which seems to be successful. It then tries (and eventually fails) the X-axis calibration. In the X-axis calibration, it first repeatedly bumps the print head against the left side of its range (around 0mm X). Then it begins to move the head a bit to the right (a few cm from the left side of its range). Then it move the print head all the way to the right end of its range, and the displayed X-value increases to around 212mm, but then it suddenly changes back to near-zero as the print head is on the right. So, then the head is on the right side of its X range, but the X-value is reading close to 0mm. It proceeds to bump the head against the right-hand side for a while, then apparently decides that it has failed the X calibration test. It then conducts and passes the Y calibration test.What is going on? Initially the system displays a reasonably large and positive X-value as it moves the head to the right. But, then it just abruptly changes to near-zero. So, the head is all the way to the right - repeatedly bumping against the right-hand side of its range - and the display shows an X-value close to zero - as if the head were on the other side. What causes this? The printer is almost new. I purchased it a few weeks ago, but have not been using it until the day before yesterday. That is, I took it out of the box and set it up Saturday. The calibration went fine then. Over Saturday and Sunday I did several prints (maybe 4 or 5). Then, Sunday night, it produced an error as it prepared for another print, so I power-cycled and did this calibration test. There does not appear to be any debris on the belt or rail, and the belt tension seems fine. Today is Monday.I recorded a video that shows this entire test - from the power-on until the test reports a fail. I will post it here if there is a way to do so.

Unsure if this is even close to the "official way" of solving this problem, but here is how I got it solved, maybe works for you as well.Using "moving axis" dialog, set the X to go to 0 and Y to 0 as well (for now disregard where they physically are; important is to have the set values to zero); then "Disable Motors" and manually push the printing-head all the way to the left; push as well the printing-bed all the way back. Then perform a "XY calibration" and/or "Auto home".
It shall solve the issue... 

first issue got out of the box, looks like bad experience, but seems to be gone after firmware upgrade from 5.0.1 to 5.1.2, first print started, now wait & see.

I went through all these steps and am still getting this error. The XCarriage goes all the way to right and repeatedly hits the side for about 5 seconds then the software crashes and reopens to this error. Any additional ideas would be greatly appreciated. It's as though it is not recognizing the x carriage is all the way to the right even though it is.