Nozzle heater check failed  

RE: Nozzle heater check failed

I also swapped my Cu block out for the original Al one, not just removed my sock. So it's as close to stock as it can be, even though it's got the better heater core and Revo nozzle.

RE: Nozzle heater check failed

My upgrade also failed the nozzle heater test. 178 degrees in 3 minutes, but not quite up to the target 180 degrees. It turned out that I had the hotend fan and part cooling fan wires reversed. I may not have been properly paying attention when the self test asked if the fan on the right was spinning. 

Swapping the fan wires inside the electronics box made everything good. Who would have expected that turning on the fan allows the hotend to come up to temperature faster. Maybe it has something to do with the location of the thermistor. Turning on the proper fan allows the temperature to be measured more accurately.

Steve

RE: Nozzle heater check failed

Just to close this out the soldering iron trick worked.  Put on the fat blade tip and was able to get the hot end up to temp fast enough to pass.

RE: Nozzle heater check failed

- Are you using the 60W 3.5 FW on a 60W REVO heater ?

It seems like you are using a 60W 3.5 FW on a 40W REVO heater, and it expects a very quick heating...

Posted by: @grimbeaver

Looking at the code it has to hit 180 in 60 seconds.  I am at 178 when it fails and then after it fails and goes into cooldown it briefly reads over 180.  So I am only 1-2 short of passing the test.  This is very frustrating.  It appears I can not setup Prusa Connect either until I pass the self test.  Is that also why the firmware will not update on the WiFi module?  I tried wired ethernet as a workaround and the printer will not get the time and adding to Prusa Connect comes back refused.  Seems a lot might be tied to passing the self-test.  I can print though if I dismiss the warnings.

RE: Nozzle heater check failed

Hello,

I just updated my (working) MK3S+ to MK3.5 and have also the same issue, it fails at ~165°C

I tried with and without the sock.

I have no 3rd party parts.

The fan tests is working as expected (no inversion in wiring).

Any official statement regarding this?

Thanks!

RE: Nozzle heater check failed

This worked for me. it was the sock!

RE: Nozzle heater check failed

Ran into this issue with my Mk3S running a Dragon hotend, when upgrading to 3.5. "Fixed" it by telling it it's wearing a sock (which it isn't), which made the test pass. Wish I could do the same on my Minis with Dragon hotends. I'm really not a fan of this thermal protection model. Of course I like the idea but I don't understand why they don't offer a way to bypass it in some kind of expert settings for people who know what they're doing but don't use the standard hotend or a Revo.

RE: Nozzle heater check failed

They do let you use non-standard parts but it requires you to modify and run your own version of firmware. 

I had a similar issue after upgrading my mk3 to mk3.5. Speaking with support, I got told that the new restrictions to running a higher power heater were 'safety features' while at the same time being told that you can still use high power heaters if you modify the firmware. 

So is this new feature (not present on the Mk3) a safety feature if you can still use high power heaters on the Mk3.5 just like you could on the Mk3? If it was a safety feature, why even allow the higher power heater at all? And if safety was a real concern, why force the user to modify firmware to use the heater? Isn't that a perfect receipe for the user getting something wrong and increasing the chances of creating a dangerous situation? 

Or is this new feature there for something other than safety. To modify the firmware, you have to permanently alter the buddy board. And Prusa state that if you do that, your warranty is void (irrespective of whether a future failure is your fault or prusa's fault). So.... the new safety feature doesn't make the printer safer but it does eliminate one more printer from a potential warranty claim for Prusa. 

Conclusion - the new safety feature is just Prusa trying to reduce their costs, unfairly in my opinion, at the expense of the user's ability to use their printer in the way that they decide to use it. 

RE: Nozzle heater check failed

So is this new feature (not present on the Mk3) a safety feature if you can still use high power heaters on the Mk3.5 just like you could on the Mk3?

Yes. Nobody mention that the standard MK3S power supply is bare enough for the printer and the E3D V6 40W cartridge, but replacing the E3DV6 with a strong 60W cartridge it adds 20W more, and if there is also the MMU connected this could cause problems.

When you mod the printer, then you take all the risks.

If it was a safety feature, why even allow the higher power heater at all?

When E3D released the REVO fast change Nozzle they worked with PRUSA to create two additional FW for the MK3s (one for the 40W and another for the 60W).
At that time those FW were "approved" and signed with the PRUSA digital signature, and they could be loaded on the board without any restriction. Moreover they were also supported in Github.

However the party didn't last long: almost immediately they came out issues, and PRUSA was too busy in releasing the MK3.5 FW and fixing the MK4 FW too, so the priority to support REVO and fix issues was zeroed.

But may be PRUSA realized after releasing the initial FW 60W, that all the thermal runaway issues with the 60W were caused by some PSU which did not provide enough power to the cartridge, and they did not want to open discussion with their commercial partner E3D that did not disclose that risk to the users (e.g. the REVO kit should have included a new powerful PSU too...), so they just skipped the matter, since REVO was not a PRUSA standard product on the MK3. This type of compatibility experiments should be done by the vendors, that should ensure their products could be installed on a printer without causing issues.

Since then, they never released a MK3.5 REVO 60W version FW.

PRUSA told me that in this moment they are too focused on supporting only original PRUSA product, but may be they were concerned by the PSU supporting the Buddy+MMU3+60W 😣 

And if safety was a real concern, why force the user to modify firmware to use the heater?

This open a new scenario: the 3D printers manufacturers can't and wouldn't support 3rd party products, so all the 3D printer's accessories suppliers will need to start to release and support custom firmware for all the printers on which they want to install and sell their product; the alternative is that they will sell just few dozen pieces to some guru makers.

Or is this new feature there for something other than safety. To modify the firmware, you have to permanently alter the buddy board. And Prusa state that if you do that, your warranty is void (irrespective of whether a future failure is your fault or prusa's fault).

Both, safety and company interest. As explained who decide to mod a printer should do it at his own risk. Any liability for damages must fall on the person making the changes, and when a mod is done.. the warranty is gone!  😜

We spoke here about E3D REVO just as example, but the same rules applies for all the myriad of nozzles and extruders for the MKx (Roto, BondTech, Orballo, Micro-Swiss, etc.).

In my opinion PRUSA has been too benevolent with a lot of users to whom they sent free spare parts that should have been considered as paid consumables  or that could have been damaged during a wrong assembly of the kits. 😉

Regards

RE: Nozzle heater check failed

Yep - kept failing with physical sock on and "sock on" in settings. Took physical sock off and turned set "sock off" in settings and it passed the test easily. Thanks!

RE: Nozzle heater check failed

Wanted to just share that this worked for my upgraded printer as well.  The key was to set the printer to believe that a sock was present, but to actually remove the sock. After that the test passed, having already wasted a ton of time diagnosing it as a hardware/wiring issue.

Posted by: @foxrun3d

Ran into this issue with my Mk3S running a Dragon hotend, when upgrading to 3.5. "Fixed" it by telling it it's wearing a sock (which it isn't), which made the test pass. Wish I could do the same on my Minis with Dragon hotends. I'm really not a fan of this thermal protection model. Of course I like the idea but I don't understand why they don't offer a way to bypass it in some kind of expert settings for people who know what they're doing but don't use the standard hotend or a Revo.