Limit switch please help

Just got done putting this together and I’m receiving this error.

GRBL ERROR homing failed pull off didn’t clear. please help

What machine is this on?

Does the machine move at all when you ask it to initialise?

If you go to the settings page of Carbide Motion you’ll be able to see which of the limit switches is on and giving the issue.

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yes machine moves front to back but head just vibrates.

Do you mean the spindle doesn’t go left or right on the X beam?

Is the spindle at the far left or right end of the beam? (if so then with the machine powered off slowly move it to the middle to see if it will move on it’s own)

Did the Z (spindle) go up and down at the start of the initialisation?

yes z goes up and down and when i put it in the middle it just moves up and down and vibrates . and this is a shapeoko 3 xxl just assembled

A couple of thoughts.

The initialize sequence is Z, X, Y. If things do not go in that order, you likely have the motor cables connected wrong. If the system expects Z to be moving but X is moving you’ll get an error and some nasty noise because Z never reaches the limit sensor.

Assuming you have a system with proximity sensors, you can use a piece of metal to test the sensor. The light will turn red.

Bonus. If you have carbide motion open and settings open, it’ll tell you which sensor it’s catching


Does it vibrate because it can’t find the Z-axis homing switch? Or because it’s trying to move the X-axis and can’t?

Let us know at and we’ll do our best to work through this with you.

its trying to move ive messed with the belt tension and rollers but cant figure it out and i get a homing error

Could you describe the sequence as the machine tries to do it’s initialisation in a bit more detail?

First the Z should go down a little, then go back up to the limit switch and find top.
Then the X and Y should go to the rear right of the machine and find their limit switches.

How far through this does your machine go?

yes i hit the initialize machine z moves down then up x and y moves slowly to the back and stops and z just makes noise and vibrates

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and i get a homing error

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So if I understand correctly the machine does Z down up, then tries to do the left / right & front / back move but doesn’t move left / right on the X beam, just makes a nasty vibration.

If that’s correct then it sounds like your X stepper motor wires are not connected properly, specifically one or two of the wires are not connected, can you check through the wiring from the board to the motor and make sure all the connectors are well seated?

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yes i will do that now

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they are all connected tightly

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i can see if i can attach a video

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The easiest way to do that is to post it on YouTube as an ‘unlisted’ video and get the link to paste in here.

Does it move to the back right corner?
Sounds like an issue with a limit switch.

no doesn’t moves at all is there a way to post a video other then youtube i cant figure that out

Ok. Is it the Z still moving? Or does the Z move up, down, stop. Then the XY moves?
Sorry, it’s just not clear above.

ok i think if you search Dennis Groh on youtube you will see a video under my name