Just finished my rebuild of Gen1 MPCNC. I am able to jog the head in all correct directions. I successfully drew a crown. My issue is with homing the Y axis. X axis goes until it hits the endstop perfectly. The Y axis pauses and then moves about an inch in the Positive direction (wrong way) I know the plugs are not in backwards since i can jog in correct direction. I am running a Rambo Mini 1.3 with stock firmware (hex file) and Repetier Host (latest version). Any ideas?
The proceedure for homing X and Y goes as follows:
Travel towards the axis minimum until the switch reads as triggered (> 2.5V on the signal line, typically.)
Back off from the switch.
Travel back towards the axis minumim more slowly until the switch reads as triggered.
The switch should be normally closed, and short ground to the signal line. This keeps the voltage lower than the trigger point. The switch being triggered opens thst circuit up and internal circuits raise the voltage on the signal line above trigger theeshhold.
So the upshot is that if the wires going to the stop switch are interrupted, the machine will read that switch as triggered all the time, and you will get the behaviour that you have seen.
Check that the wires at the switch are correct. Microswitches typically use the outside two pins, and not the middle one. Check that you are connected to the (S) signal and (G) ground pins on the mini rambo. If there are any wire extensions, check that they are making good contact.
The Gcode “M119” sent from the terminal will tell you if your end stops are open or trigfered.
Dan, Thank you so much for replying. I took your advice and m119 show y axis triggered. Even when I unplug the wire from the Rambo mini it still shows triggered. So now I have to figure that out. It’s a brand new board so I’m not sure how to proceed. Wish me luck googling 
That’s normal.
Check the switch wire. There should be continuity between the terminals when the switch is in normal position, and none when it is triggered.
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OMG Dan you saved me soo much time! It was one of the wire leads from the manufacturer. Swapped out for a fresh plug and now it works like a charm. I was looking up how to remap pins on the Rambo…so once again, Thank You Sir!
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