Crash Detected
I've had this error happen a few times now, it's happens when I start a print and the printer is doing its normal warm up in the front right corner.
The error comes up on the screen, stays for a few seconds and the printer carries on and prints fine. I don't have to clear the error, it goes away on its own.
I'd say it happens about one print in 10.
Any ideas whats causing it ? Anything I can check ?
I assembled the kit version of Core One, batch one, so it's been up and running about 3 weeks or so.
RE: Crash Detected
I have not yet heard of the error with the Core One, so I would say it's best to write to support.
RE: Crash Detected
Mine did this once but not since,what surprised me was that it was during the normal headbanging session when I would expect this feature to be turned off, is is kind of no surprise that it bangs into things when intentionally raming into ends. It has not done this since that one time.
/Anders
RE: Crash Detected
I can’t print at all. When I try to I get errors about not being able to home the printer, or a printer collision has been detected . Either way the printer is unusable and a waste of money,
Contact Prusa Support via chat. You will need your printer's serial number.
Cheerio,
RE: Crash Detected
There seems to be quite a big issue with the hotend heater and the loadcell signals (homing, probing, nozzle cleaning).
But there's also the issue regarding a little gap in one of the corners, if you move the gantry all the way to the front or back, which needs some squaring/bending and belt tuning.
If the issue is only, when starting a print (hotend heating up!), then try the custom Start G-code from here:
https://forum.prusa3d.com/forum/postid/751199/
Credits to everyone here: https://github.com/prusa3d/Prusa-Firmware-Buddy/issues/4596
And to @David.b36 https://forum.prusa3d.com/forum/profile/david-b36/
If the issue also happens, when the printer is cold and you start a homing from the LCD panel, it's probably the gantry not being perfectly square.
If both solutions don't work, a cable might be pinched or something more serious, like a faulty board etc.
RE: Crash Detected
Thank you for posting about the headbanger session, I thought mine was stuck in a loop! It has eventually worked the metal urges out and is printing.
RE: Crash Detected
I had this problem also 3 times....Done a reset and everything ok.
RE: Crash Detected
I have unboxed second Core One yesterday and it is having issues with crash detections. From 5 prints two had issues with crash detection. Bed was mowing up and down and was slowly getting lower and lower. So my gues would be some resistence in Z axis that is triggering TMC drivers of stepper motors.
RE: Crash Detected
After some diagnose with support it seems that load cell on our printer is bed. Probably badly crimped connector. Values in steady state were -5200 and sometimes around 0.
RE: Crash Detected
Just got off support chat and it seems I have the same issue. I noticed the static value of the load cell varying wildly. It changes depending on where the extruder is as well. It started with consistent nozzle cleaning failures(hoping this is related), then progressively took longer for the bed to reach the nozzle. Stopping midway to the nozzle, as if it hit the nozzle, then slowly moving upwards again, before repeating the process. I also noticed the nozzle hovering above the bed on multiple of the nozzle cleaning points. Sometimes I get the collision error, sometimes I don't. I was getting readings of -4500 and -45 in standby. Keep me posted on your situation. I am going to remove the load cell tomorrow and inspect it. Hopefully the new one shows up soon. Truthfully my CORE One has been an absolute nightmare from the start.
RE: Crash Detected
Disassembled the extruder and removed the heatsink/load cell. All the terminals on the connector are seated and look good as well as the cable itself. There is a void with something protruding on the sealant where the load cell is located. Unsure if its enough to cause a failure. Still waiting on shipping confirmation on the replacement hopefully it comes soon. 
RE: Crash Detected
After 10-20 prints i get this same problem...
The printer constantly reports a collision before printing, and it can't properly home the Z axis, which takes several minutes. I disassembled the Z axis drives and checked the lead screws. The drives operate smoothly and move fully in manual mode – calibration was completed without any problems. The only thing I noticed is that the strain gauge readings fluctuate – unfortunately, there's no description anywhere of what the correct readings should be. Does anyone know?
RE: Crash Detected
Same probleme here, the printer completes Auto Homing just fine but when I start a print it can't find it's Z-axis.
Spent two hours trying to find a solution, ended up reinstalling the firmwear on the US-stick and it started printing right away.( no hard reset, just the firmwear from the website).
RE: Crash Detected
Re-running the loadcell calibration can help (the one where you put your finger against the nozzle, when asked to do so).
But for me, disabling the hotend heating for all G28 and G29 commands in the Custom Start G-Code solves it completely. Just search for it, there are explanations and complete Start G-Codes available by other users (or me).
M104 S0 ; disable hotend heating
Sadly, there seems to be an oversight by Prusa regarding the ground connections inside the print head and the loadcell goes a bit crazy, when the hotend heater is active.
RE: Crash Detected
Re-running the loadcell calibration can help (the one where you put your finger against the nozzle, when asked to do so).
But for me, disabling the hotend heating for all G28 and G29 commands in the Custom Start G-Code solves it completely. Just search for it, there are explanations and complete Start G-Codes available by other users (or me).
M104 S0 ; disable hotend heating
Sadly, there seems to be an oversight by Prusa regarding the ground connections inside the print head and the loadcell goes a bit crazy, when the hotend heater is active.
I attempted recalibration of the loadcell and it did not help in my case. It turned out one of the solder contacts was lifted from the sensor prior to the white sealant being deposited. That is what is protruding in the photo. When I get the new heatsink/loadcell I will attempt disabling the hotend heater. Sharing the ground for the loadcell with PWM heater is unfortunate. I'm guessing theres a limit to the amount you can mask that by massaging the firmware. Especially with the additional load on the sensor from mechanical strain via the main cable/filament tube. I was getting 4k spikes from barely manipulating the cable. Although I am unsure if that was solely due to the poor connection on my damaged loadcell.
RE: Crash Detected
Our printer is now fixed.
After replacing heatsink with load cell sensor first print was fine and next one failed again. So back to support.
This time they send me new cable between extruder and main board. And now printer is working two weeks without issue.
I seems, that one wire was badly crimped.
I guess that in future CAN bus upgrade will be popular option. Just four wires for extruder.
RE: Crash Detected
Our printer is now fixed.
After replacing heatsink with load cell sensor first print was fine and next one failed again. So back to support.
This time they send me new cable between extruder and main board. And now printer is working two weeks without issue.
I seems, that one wire was badly crimped.
I guess that in future CAN bus upgrade will be popular option. Just four wires for extruder.
I'm happy to hear you are back up and running.
I believe there are a few others who had the same symptoms and replacing the main cable solved their issues as well. Were you able to pinpoint the bad connection in the main cable? I ask because the more I look into this issue the more I suspect the problem might be mechanical strain from the harness being mounted on top of the extruder assembly.
I'm wondering if the act of rearranging the main cable and its routing/positioning by installing a new one results in a a set up with less strain transferring to the load cell, allowing normal behavior to resume.
The printed part that guides the main cable is tall and acts like a lever. With the strain from the cable bundle and filament tube, the load cell registers the stress. Add in the interference from the the nozzle heater and the load cell value goes out of the allowable range during nozzle probing.
On the MK4S the main cable is mounted at the bottom in a much more solid location of the linear rod carriage. I tried pressing on the cable mount on the MK4S while watching the load cell reading and it only registered about 30 above the static reading. The load cell wiring is also routed on the opposite side of the hotend heater cables, potentially reducing interference compared to the C1.
If anyone is curious and wants to press on the cable to see what kind of a spike in the load cell you get, as well as moving the extruder to several X/Y locations and noting the difference. I think it would be valuable information.
At what stages the load cell is reset or the values "tared" during various functions, and how the values are handled is information I don't have.
When my new heatsink/load cell arrives I will try to dig in and find out more. It seems more and more people are experiencing this issue so I hope it will be addressed soon.
RE: Crash Detected
The reading from the strain gauge sensor is fluctuating. It doesn't matter if it's hot or cold. I'm waiting for a new one to arrive.
@Wojta, do you know which wire was bent or damaged too much?
RE: Crash Detected
I ended up having mine sent to a warranty repair company in the USA called Printed Solid
I expect to to get it back this week but here was the notes from the repair tech.
Tech Notes, We went over your printer to verify all was in perfect operating condition after the replacement of the "nextruder Cable" which was the affected part causing your issues. We did several test prints (Included) in both PLA and PETG to verify proper operation of your printer.