Lulzbot Mini 1 - Z Axis issue :(

So was cleaning my hot end with a wire brush (why didn’t I read earlier!) and wonder if I have blown the rambo board :frowning:

After firing up the printer to print something I noticed the printer wasn’t doing the auto leveling process properly and when trying to send commands to move the bed noticed it wasn’t moving backwards but it would move forwards.

I’ve followed this post - - and disconnected the wires to the end stop but still getting the following when running the M119 command:

< Reporting endstop status
< x_min: open
< x_max: open
< y_min: TRIGGERED
< y_max: open
< z_min: open
< z_max: open

Can anyone recommend what to check next?

Seen some other posts about checking the hot end for shorts but not sure what else I should check for. Thinking back I think I may have done this as the printer reset itself and OctoPrint had a status message saying it had been reset.

Really hope I haven’t blown the board :frowning: Don’t want to open up the side without following some prescriptive instructions this time!

The RAMBo has several replaceable fuses, one of which may be blown. It’s a brown, 5 Amp automotive blade-style fuse. Try swapping the two brown fuses, it may be F3 in this image:

Reach out to the support team for help at

Thank you for your help :slight_smile:

Opened it up and checked the fuses none appear to be blown I swapped them around as well and the M119 command still shows being triggered.

I take it next option is to get a replacement Rambo :frowning: any way to ensure I won’t short it out again when installing the replacement?

Also I’ve seen something about estops? Is this something I should be concerned about?

The party line is don’t clean the nozzle with anything that can conduct electricity.

I took a slightly different approach and carefully applied some Permatex Red RTV High Temp Gasket Maker around the wires. The temperature range of this product covers the temperature range of the nozzle.

Temperature range -65ºF to 650ºF (-54°C to 343°C)

Thank you for the advice :slight_smile:

Got the new RAMBO board, seriously who designed the internals of the thing! The wiring looks like a HR giger painting.

I rewired the printer as per the instructions but now have an issue with the Z axis not moving and making a screeching noise when using the cura controls.

I’ve uploaded a video to YouTube as easier to see what is happening -

Anyone got any ideas? I’m about to launch it out of the window! I’m in the U.K. so don’t have an option to send back for a repair … may end up flogging it for spare parts.

Any advice appreciated!



Reach out to the support team at They’ll be able to see where you’re at and recommend the next steps. There’s two different Mini 1 versions, with some wiring differences.