Bit setter not working

I just got a new Shapeoko pro XXL and I’ve been trying to get everything initialized but I’m having trouble with the Z axis. When it leaves the home position it goes to the front center prompts a bit changes, it then goes to the bit setter centers starts down and never stops until router is pushed up and Z drive crashes. I have gone through about everything I and youtube can come up with with same results. I’ve checked the wiring, all connectors, and verified every step results always the same, any suggestions

First and foremost, contact

You need to check if your Bitsetter is working:

  • when you push the bitsetter buttton manually, does the LED light up?
  • if so, open Carbide Motion, connect but do NOT initialize, then go to the Settings page. There is a line there called “GBRL active input pins”. Does it display “PROBE” when you push the bitsetter? If not, something is wrong in the bitsetter wiring

The bit setter doesn’t light up

Ok, so either it is defective or (more likely) something is wrong in the wiring or connector at the controller side.

When you assemble the machine, did you properly connect the BitSetter extension cable before assembling the front right plate? (black sleeved wire in the pic below)

Can you take a picture of the bitsetter cable at the controller side ?

Do contact support and they’ll sort this out for you.


I wonder if CM should support a “pre-flight” check option for new machines to catch these sorts of situations before motors start to grind?

This could be a sequence of “Put a spanner near the [n] Axis proximity switch” queries and end with a “Push your BitSetter button” query.


I noticed on my bit setter the button was a bit stuck. So I put the button side down against my workbench and put pressure on the back. It felt like the button was stuck. After it got unstuck the button freely moved up and down.

Yes, so this confirms that the bitsetter signal is not seen by the controller. What about wiring inspection? Did you contact support?

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