HELP I used my bot yesterday and all worked fine. I turned it on today and the z doesnt work . it will not go up or down so i looked thru 27 pages in troubleshooting and didnt find the answer. I have a prt alpha 2002 i swapped the wires from the y axis to the z and the motor responded fine. opened the control box all drivers have green lights on . I noticed that where the usb cable goes to the serial port there looks like a small yellow light that is not on? the x and y both work in keyboard mode but the z will not move . I also tried to do a c2 and nothing . can a usb cable go bad ? could that cause this problem?
on the back of the circuit board there is a square that looks like a readout for a number display there is a small red light on one corner that is lit is that normal? could it possibly be a loose wire? Thank you for your help