Stepper Motors freeze after first few layers of print

I have been seeking help on an issue I have faced now for several months on my
Prusa i2.

Details:
NWRepRap kit. Prusa i2. RAMPS1.4, Windows 7 using Slicer and Pronterface,
250000 Baud.

Symptoms:
S1: Printer will stop printing after the first or second layer.
S2: RAMPS board has indicator light that continues to flash as if data
is received from PC.
S3: PronterFace continues to run and appears to be be communicating with
RAMPS board.

Tests and results:

Test1: I have compiled multiple small stl files. Different 2X2X2mm as well
as a STL provided by someone who has used it within a successful build on
their system.

Result1: Printer will run and appear to print up to a given point unique to
each geocode file. First almost completed the first layer, second had a
thinner first layer but would not exceed 3rd. Last was circular and got to the
2nd layer the stopped. When the Extruder stops it appears to freeze and all
motors no longer respond. Leaving unit alone has not resulted in print
continuing.

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Test2: Concern was made around extruder over heating. Edited Geocode and
disabled heater so that printer would run under heater temp and not triggering
extruder motor. This test was to prove if the issue is due to over heating
extruder causing the unit to halt.

Result2: Found that the printer would go through the same print pattern and
halt at the same spot without extruder engaged in the process. This is
believed to exclude extruder head as trigger point for freeze.

Any recommendations or extra questions to help is deeply appreciated.

For a given STL file, does the print freeze at exactly the same point each time you try to print it? If so, that suggests a problem with the firmware, or with the host program if you are not printing from SD card.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Someone else had a very similar problem a couple of weeks ago.
Have you seen that post?

In short.
His motor drivers were getting too hot by that point in the print that it stopped and tripped the failsafe in the stepper driver boards.

Have you tuned the stepper drivers with the trim pot?
If not do so and try again.
They do have hest sinks, dont they?

If you have, try aiming a fan at the controller heat sinks.
A desk fan will do as long as it has continual air flow over the heat sinks.
Try printing again.
If this fixes it install a 12v fan to keep the heat sinks cool.

Good luck.

Gordon

Thank you DC42 for the reply.

To confirm, the prints do stop at the same place each time depending on the geocode file used. In other words, the first geocode I used stopped at the same place consistantly. I started with the firmware software recommended by NWrepRap and then was suggested to try Merlin as a result. This switch of firmware software did not address the issue when testing. I will go ahead and go through again the firmware compiling and see if anything fleshes out from there. Ill also run through a print and sample temps on the motors and components to see if I am running into any over heating issues.

I have been told that this is a strange one by others leading me to question if I have some RAMPS board issue. Best way to test that is to switch it out but thats far from a cheap test. However one that Im running out of options but taking.

Apriciated again all the feedback. I will update this thread with additional findings and hopefully the fix once found.