Auto level not working

Hello everyone !

Since few months, Auto level is not working on my UpBOX.
I have try with two software “UpStudio” installed on two different computer, same issue.

i’m pretty sure that 5v is not send to the uC behind the head, to control the servomotor’s controller.
Anyone have the same problem ?

Thx :slight_smile:

Make sure when you perform an auto-level that the servo is actuating so the limit switch can touch the bed.

Some times these servos die on the UP Box, I don’t know why, but if the servo is unpowered when the machine is on, before selecting auto level in the software, you can try manually moving the servo arm for the micro-switch to touch the bed. Just remember to move the servo arm back up again after it’s done it’s nine-point bed probing otherwise there’s a risk of the micro-switch on the end of the servo arm getting damaged.


Thx for answer.

Servo is working, i’m sure.
I’m also sure of that :
CPU (via the motherboard) send a command in 5V to the extruder’s head. A microcontroller on the head transform this 5V signal into a kind of PWM to command the two position of servomotor : Up or Down.

I dont receive this 5V command to extruder’s head.
My flat cable is OK, the 5V is also missing on motherboard connector.

If i can know how is running this pin on the motherboard, i could know it it’s a hardware problem or software prob.

Thx all.

Hi ! little up for my topic. Any idea ??

I read your post just today while searching for another topic, and thought I’d chime in as well, just in case something may help your issue.
We’ve recently serviced an UP BOX+ that ad this very issue (request for Auto Calibration results in no servo flipping down, and printer just moves to the 9 points, but no measurements are taken). In this case, the servo was newly replaced already, and the small ribbon cable running to the servo was also tested as working.
My next assumption was the wider, white FFC ribbon cable from the back of the printer to the toolhead (Since this is a consumable part that does often get replaced in the UP BOX+ printers that get frequent use). Upon testing with a different FFC cable, we found that the FFC converter (the small PCB at the back of the extruder) was the actual culprit.
Whether you’ve ever swapped out the FFC cable in he past or not, the connector on the FFC converter board where the FFC cable connects, can become an issue over time. These FFC cables can get a fatigue spot, usually along the edge of the extruder, when the extruder is extending and bending the FFC cable the most (when in the front left position of the print bed). After some time, the FFC cable can begin to faulter. If the FFC cable isn’t your issue as you had stated from your testing (keeping in mind a single trace within the FFC cable could be bad, leaving the other traces intact) then I would certainly consider the FFC converter board. All of your data that controls the Z auto calibration probe goes through this FFC converter board, the FFC cable and the small Z probe ribbon cable.
I hope this information is in some way helpful in your resolution.

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I think MakerTree3D could be right. I also had quite some issues that had to do with that damn cable and board. I was never a fan of the automatic calibration and recommend leveling the platform manually and resetting the calibration values.

I changed the FFC cable on my Up Boxes to a simple cheap flat cable and never had any issues again, only thing is the platform sensor is disabled. Check this:

I connected the flat cable to the filament tube with a small clip I shared here:

So if you want to fix the sensor check the FFC/FFC board and otherwise I would recommend switching cables.