[hitnrun75]

Hi all, new here and to CNC/Machining in general. Built a 4 axis from a Grizzly x2 with kl-4030's and a c10 BOB. Using a UC100 motion controller. X,Y,and Z no trouble but when I connect motor to A I get no motion on A. Locks up fine and XYZ are unaffected. I replaced the KL-4030, and have tried different combinations of motors and cables. I know the motor and cable are good and all of my voltages are doing what my XYZ are doing. I'm using Mach 3. Any advice on troubleshooting? I'm good with a multimeter but that is really the extent of my available testing equipment and about the only thing I can come up with is that my c10 is bad. DRO in Mach shows movement, and as A is wired the same as XYZ I am running under the logical assumption that it is the c10 but I don't want to order a new board without seeing if anyone else has run into this. All 4030's are set for half steps and my power supply is rated at 9 amps, I've kept my total Amps under that and I'm using a separate external 5v 300mA power supply for the c10. It's actually the 4 axis kit from automation technologies with the 425oz steppers. Thanks to any and all who reply.

[doorknob]

Is your A axis connected with pin 8 for step and 9 for dir?

If so, can you put your multimeter probes (measuring voltage) between pin 9 and GND (on the output of the C10), and then use Mach3 to jog the A axis in one direction and then in the other direction? You should see close to 0 volts when jogging in one direction and close to 5V in the other direction. If you don't see the voltage change when the direction changes, try probing the input to the C10 (right at the DB25 connector) to see if the voltage changes there. If there's no voltage change at either the C10 output or the C10 input then you might want to focus on either the Mach3 configuration or else the UC100.