Bed Leveling Error

I have a Lulzbot Taz 6 that has a bed leveling error that causes the machine to spit out “Probe Clean Failure” error. I have performed all the suggested solutions for the Probe clean problem:
-Wiped nozzle with brita pad
-Reflashed firmware
-Recalibrated X-Axis
-Unplugged and replugged printer in

The printer will home properly when the print starts. Then it will wipe the nozzle. When it gets to the next front washer, it will tap it and then slowly wind down and touch it again. Then it heats up to wipe nozzle again. It will do this several times until it says “probe clean failure.” When looking at the debug console, I don’t notice anything. I did happen to watch the LCD screen when it was performing the cleaning, and noticed right before the “Probe Clean Failure” a brief message saying “Bad bed leveling” will pop up.

I think is may be an electrical issue but do not have a multimeter to prove otherwise. What are some suggestions that I may have not tried?

I am having the basically the same error. It was printing fine and then started throwing this error forcing me to cycle power. I even took the head off and made sure the nozzle was shiny clean.

For me it does the first two washers fine (fast touch followed by slow touch). When it gets to the third washer it does a fast touch and then the LCD says heating nozzle and it goes and wipes the nozzle. It goes through this loop three times and then says Bed Leveling failed and give me the Probe Error

Make sure the bed-leveling washers aren’t loose (e.g. I have removed and re-inserted the bed and failed to re-snug the bed leveling washers before).

They don’t need to be cranked down crazy tight … just neatly snugged.

Grab a multi-meter put probes on a couple of corners at a time to verify that you get good conductivity from one corner washer to the next corner washer. It should read less than 1Ω of resistance. If it reads high, the washer is either loose… or dirty (you can remove the washer, screw, clean it all, then put it back on.)

On a TAZ 6, the zero sense wire is a single red wire attached to the heater-block on your hot-end (the heater cartridge that heats up the hot end is a pair of red wires that are much thicker wires… not those wires. You are looking for a single red wire secured with a screw on the side of the heater block). You can touch 1 probe to that screw and another probe to the tip of the extruder nozzle to make sure you read less than 1Ω resistance.

If all that probes out nicely… then you could have a damaged wire going back to your control board. The bottom of the bed has a screw holding a wire (the metal bed plate connects all four bed washers to the wire attached to that screw). That leads to the wire harnesses that eventually connect it back to the board so you may need to trace it out and do a basic continuity test along the wire to make sure you don’t have a break.

I had a different wire break on one of my printers … the wire physically appeared to be fine in that it had no breaks nor any physical signs of damage or stress… yet did not pass a continuity test end-to-end. I had to replace it (or you could splice in a wire if you can find the point where it broke.)

With power off turn one of you Z axis rods left or right as necessary to move the X axis carriage up or down as necessary. For now an eyeball adjustment may be all that you need to get it working, when you have it working again print these things from thingiverse to do a quick level adjustment,

I too have experienced this problem. The Z axis motors get out of synch from time to time. 1st washer test successful, 2nd washer appeared the same, a quick tap, raise up, think about for a few seconds and then decided that it failed, repeat 2 more times and flag it as a probe failure. I never looked at the console or LCD screen for errors. After a quick re-level it was working again. There’s many methods to try and get that perfect level. These are a good starting point and sometimes is all you need.

If you own a 3D printer you should also own a multimeter. Try this one for less than the cost of a spool of filament.

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