Y-Axis moving too fast, too far

Let me start by saying that this machine has been working very well for the last 4 months. I even made a carving last night and it went perfectly.

This morning I turned on the machine and after connecting I ran a homing cycle. Right away I noticed that the Y-axis was moving really fast. The X and Z axes were fine. First think I did was check the GRBL settings which I found had not changed.

Upon further investigation the Y-axis is moving approximately 3mm when I tell it to go 1mm. It also appears to moving too fast, much faster than before. I refreshed the Arduino and even moved the GShield to a second Arduino. No change.

I then switched the X and Y cables on the GShield and the problem moved to the X axis. Y was fine now.

I don’t know what else to try. I tried both UGCS and Easel with the same results.

Might I have a defective GShield ???

As always any and all help is appreciated.

Very high probability the gShield is bad (most likely the Y driver chip).

That’s what I’m afraid of…

I’ll call Inventables in the morning.

Thanks Larry.