The homing cycle on the Carvey uses the Smart Clamp to zero your Z-Axis to the top of your material. Several issues can cause the switch on the Carvey Smart Clamp not to register, such as faulty wiring, a defective smart clamp board, or debris getting stuck inside the clamp and obstructing the switch from functioning properly. Start by cleaning and servicing the smart clamp as outlined here.
You'll also want to triple-check that the connection is seated properly, and if needed, disconnect the Smart Clamp PCB from its wire by removing the header pins. This will give you access to cleaning it all out with a brush and/or cloth.
Check the Machine Inspector
Next, you'll want to test if the Smart Clamp is working in the Machine Inspector. Power on the Carvey and open the Machine Inspector by going to Machine > General Settings > Machine Inspector. With your Carvey turned on and plugged in, you can press the smart clamp button with your finger and check if you are getting any input. You should see the circle under "Clamp" turn from white to green when pressed down.
If this does not fix the issue, you will most likely need to replace the Smart Clamp. The Smart Clamp is currently available on our website:
Carvey Smart Clamp