So I finally got around to installing the touch probe over the holiday.
Wired up the probe to my 2.1 Shapeoko 3 board. GRBL 1.1 upgrade already installed, Running CM 4.0.428 on a Windows 10 PC.
With the Shapeoko powered up but NOT connected to CM, the touch probe led is green, and it turns red when I touch it with the alligator clip lead. So far, so good.
Next, I fire up CM and connect to the Shapeoko. Touch the alligator clip to the probe body, LED goes to red. Good.
Click “Initialize Machine” in CM, and it homes the gantries.
Touch the alligator clip to the probe body: NO RED. It just sits there solid green.
Shut down CM, but leave the Shapepoko on. Touch the clip to the probe, no red.
Power down the Shapeoko, then power back up. Touch the clip to the probe => RED LED.
When installing the probe, I first attached the alligator clip to the shapeoko through one of the screws at the corner of the controller pcb. When I powered up, CM could not find the shapeoko at all. So I backed that out and attached the alligator clip to the aluminum shroud around the PCB, using a self-tapping sheet metal screw.
Any ideas why the probe stops working after CM machine init?