Y-axis Endstop Issue i3 pro C

[The3DStudent]

My x and z axis both move to the corresponding when I click the home axis button in repetier and then allow me to move them to the soft endstop on the other end of the axis as they are supposed to. My Y axis (build platform) moves in small increments toward the endstop each time the axis home button is pressed. Once it reaches the endstop it will move toward but not away from the endstop. If the build platform is moved to the middle of the axis and the endstop is manually triggered, the axis moves both toward AND away from the endstop. I have tried several things to diagnose/fix this issue (listed below), but I am quickly getting frustrated.
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Printer Specs
Black 8mm acrylic Prusa i3 Pro C with dual extruders
control board: GT2560 + Ramps 1.4 (I may be wrong about this, but it is what was listed in the specs for the printer and appears to match pictures)
Firmware: whatever was loaded onto the board by geeetech; according to repetier, Marlin.
PC Software: Repetier

Physical mechanical endstops at x-min, z-min, and y-max. Each is currently plugged in firmly to the port with the corresponding markings.
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Things I've Tried

Exchanging y and x endstops
Result: x- axis functions normally y-axis has same symptoms.
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Moving Y- endstop to Y-min port on control board
Result: same symptoms

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changing Y Home position in Repetier>> Printer Settings >> Printer shape
Y-home =Y-min
Result: Same symptoms

Y-home =Y-max
Result: Same symptoms

Y-home =Y-0
Result: Same symptoms

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M119 command to view endstop state:

With endstops NOT triggered
Results:
x_min: open
x_max: TRIGGERED
y_min:TRIGGERED
y_max:open
z_min:open
z_max:TRIGGERED

With all 3 physical endstops manually triggered
x_min: TRIGGERED
x_max: TRIGGERED
y_min: TRIGGERED
y_max: TRIGGERED
z_min: TRIGGERED
z_max:TRIGGERED

[zhangxueyou]

Please swap x motor driver with y motor driver to check if y motor driver is fine.
All the endstops should be connected to MIN slot.

[The3DStudent]

With the endstop open, the y axis will move as it is supposed to until it thinks it has reached a soft limit y=0 or y=200.

As you suggested, I connected the y motor to the x motor port. The Y axis function and allows me to move between the soft limits for the x axis, but obviously y axis movement never triggers the x-min switch. When x-motor is connected to y-port, X-axis behave the same as Y-axis before the swap. I tried this with the y endstop connected to y-max and again connected to y-min the result were identical.

Y-endstop on this model is at the back of the machine at y=200mm. In repetier >> printer setting >> printer shape, should y-Home be set to min/max/0

[zhangxueyou]

In Repetier, the printer setting is similar to this:

printer setting2.png (25.19 KiB) Viewed 16585 times

How is it when you control the printer by LCD, is it homing properly (Prepare>Auto home)?

[The3DStudent]

Tried this test with endstop plugged into y- min then into y-max same result from each.
when homeing Y- axis via LCD or Repetier, Y axis now moves toward the front of the machine(opposite the endstop) until it crashes into it.
I edited my repetier settings to match the ones provided prior to conducting this test.

[zhangxueyou]

How is it when you connect y motor wire in another direction?

[The3DStudent]

The connector type does not allow reversing the connection and I am not damaging the connector to swap pins without the appropriate tool unless geeetech will agree to provide a replacement connector and pins free of charge with a 7 buisness day max delivery time. I have worked with identical connectors, motors, endstops, and other hardware extensively. As the axis is behaving correctly when withing the soft endstops and only having problems homing and stopping at the physical endstop, this seems like a firmware issue to me...

[zhangxueyou]

What color is your mainboard? White is GT2560, red is Ramps1.4+Mega2560.
We will send the correct firmware to your email.

[The3DStudent]

It is a white board. As far as I can tell it is this one http://www.geeetech.com/gt2560-3d-pr...ard-p-915.html

[zhangxueyou]

Please check your email.