Z1 only moves in up direction

Greetings yall,

Could use a lil help here, in the process of building my Lowerider 2. Got everything but the ends endstops connected. Testing the motors and for some reason my Z1 will only go up. Flipped the steppers and the issue moved. Changed the driver and the issue still remained. Could use a lil guidance, sorry noob here


Have you adjusted the stepper driver voltage?

Yup, VREF is set to .87

I just read it again. It followed the motor, not the driver. So that points to a mechanical issue or a wiring issue. Steppers almost never go bad.

Does it fall on its own?

Nope holds firm. Let me explain better, when I flip Z1 and Z2 motors on the RAMPS it does the same but only on the Z2 side.

So basically anything plugged into Z1 will only go up, not down.

The machine should drop under its own weight. Something is binding. Have you lubricated the leadscrews? Or maybe they are over constrained, they can be sensitive to that. If you post a photo of the bad side, someone might notice if something is on there backwards (I’m always bad at that).

It falls under its own weight when the motors are disabled.

It will drop under its own weight, when the motors are off. It will not drop when you command it to. But that behavior follows the wires, and stepper…

You got me. I don’t see it. Maybe someone else will have a good explanation.

Are endstops connected/setup properly? If it thinks its hitting an endstop it may not allow it to lower.

I put the Z1 and Z2 endstops in and M119 shows them open and still does it.

When you move down, does the bad side hold in place or does it move up?

If it moves but in the wrong direction it suggests the DIR pin may be shorted or somehow bad, or there could be a firmware issue causing that pin to get stuck.

The bad side moves down. Would you know of a way to test to see if the pin is shorted?

Just realized I opps’d on my last response. The bad side always goes up. No matter what I do the bad side moves up. If I flip the connector for the bad side, it always goes down. I’m thinking its gotta be a bad board. If I swap the driver it still does the same thing. New board is on order now.

If you swap the cables, including the motors, at the ramps board, does the behavior follow the motor/cable/machine side or follow the board/driver?

If you have a multimeter you could try to measure the voltage on the DIR pin, which are these (second to the last on the left side as shown):

Best is probably if you unplug the drivers so you don’t accidentally short stuff.

Try moving up and down and see, if both drivers are being given the same signals. If the board is bad you might see the good axis switching between +5V and 0V, while the bad axis is stuck either on +5V or on 0V.

Yes. The issue follows

I’ll give that a shot as soon as I get home. I’ve gone through the firmware line by lone and it all looks correct. I’m thinking it has to be the board. Literally just came in on Friday, looks like it might be going back to Amazon.