Jump to content
UltiMaker Community of 3D Printing Experts

Heated bed on UM2 no longer reaching temperature


Recommended Posts

Posted · Heated bed on UM2 no longer reaching temperature

Hi all, I've been printing fine with my UM2 for many months. My last print came detached and after a little investigative work found the bed temperature was only about 30 degrees C. I haven't changed anything with my setup for about 10 months so it's nothing I've done recently.

The UM2 screen reports back a temperature of 105 (the target temperature), but it reaches this very quickly (about 60 seconds) rather than the expected 10-15 minutes). The actual temperature is about 30 degrees even after 25 minutes.

After about 30 minutes I get:

' ERROR - STOPPED Temp Sensor Bed'

I've swapped over the heated bed for a spare, but this didn't help.

Any ideas?




  • Link to post
    Share on other sites

    Posted · Heated bed on UM2 no longer reaching temperature

    Please update your settings to indicate that you have a UM2.

    Does it report the wrong temp even at room temp? At room temp it should be roughly 20C.

    The bed uses a simple resistor to measure current. Turn your UM2 on it's side and remove the 2 screws to remove the larger cover. Remove the larger cover and remove the two wires that go to the temp sensor (temp2). Check the resistance. It should be about 108 ohms at 20C. Anywhere from 90 ohms to 130 ohms is probably normal. While the resistor is connected try jiggling the wires where they go into the heated bed.

    You will probably next have to remove the heated bed - it's pretty easy - start with the 3 levelling screws. There's instructions elsewhere. Remove the 2 screws early on that hold the cable to the heated bed down at the back of the heated bed. I think those are the only 5 screws you need to remove (3 leveling, 2 hold down).

    Now be careful - there is a sticker about violating warranty somewhere on the heated bed possibly. Make sure that the 4 screws are all tight. Check the resistance at many places. The most common failur point is where the block of 4 screw connectors is soldered to the heated bed. Messing with this solder however may violate your warranty if you are still under warranty and if you have a sticker that says so. Possibly even if you don't have the sticker. I had to resolder those 4 pads and it was very simple and easy and trivial so I don't know why it would violate the warranty.


  • Link to post
    Share on other sites

    Posted · Heated bed on UM2 no longer reaching temperature

    Thanks GR5. It does read the correct ambient when cold but when heating up it doesn't. The reported temp shoots up but the actual temp is bearly warm. However I get the same result with a different plate, so I'm thinking the error is with the cable or connection at the PCB end or PCB itself.

  • Link to post
    Share on other sites

    Posted · Heated bed on UM2 no longer reaching temperature

    Well then heat it up to 40C or whatever and then cut power and measure the resistance at the PCB end (remove the wires first). If the resistance is still correct then yes it's the PCB. For temps below 60C it takes about 1 minute for every 10 degrees to warm up the plate so 3 minutes should get it up to about 120 ohms (50C).

    Here is a table showing what resistance corresponds to what temperature:



  • Link to post
    Share on other sites

    Posted · Heated bed on UM2 no longer reaching temperature

    Yep, it was this connection on the heated bed. Unfortunately I couldn't solder mine quite so easily. It failed again after 5 minutes. I can't help feeling that a connector that went through the PCB rather than one than sat on top of it, would be more reliable. This is the 3rd time this has failed for me and don't do that much printing. :-(


  • Link to post
    Share on other sites

    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now

    • Our picks

      • Here it is. The new UltiMaker S7
        The UltiMaker S7 is built on the success of the UltiMaker S5 and its design decisions were heavily based on feedback from customers.
        So what’s new?
        The obvious change is the S7’s height. It now includes an integrated Air Manager. This filters the exhaust air of every print and also improves build temperature stability. To further enclose the build chamber the S7 only has one magnetically latched door.
        The build stack has also been completely redesigned. A PEI-coated flexible steel build plate makes a big difference to productivity. Not only do you not need tools to pop a printed part off. But we also don’t recommend using or adhesion structures for UltiMaker materials (except PC, because...it’s PC). Along with that, 4 pins and 25 magnets make it easy to replace the flex plate perfectly – even with one hand.
        The re-engineered print head has an inductive sensor which reduces noise when probing the build plate. This effectively makes it much harder to not achieve a perfect first layer, improving overall print success. We also reversed the front fan direction (fewer plastic hairs, less maintenance), made the print core door magnets stronger, and add a sensor that helps avoid flooding.

        The UltiMaker S7 also includes quality of life improvements:
        Reliable bed tilt compensation (no more thumbscrews) 2.4 and 5 GHz Wi-Fi A 1080p camera (mounted higher for a better view) Compatibility with 280+ Marketplace materials Compatibility with S5 project files (no reslicing needed) And a whole lot more  
        Curious to see the S7 in action?
        We’re hosting a free tech demo on February 7.
        It will be live and you can ask any questions to our CTO, Miguel Calvo.
        Register here for the Webinar
          • Like
        • 11 replies
      • UltiMaker Cura 5.3.0-Alpha 🎄 Tree Support Spotlight 🎄
        Are you a fan of tree support, but dislike the removal process and the amount of filament it uses? Then we would like to invite you to try this special release of UltiMaker Cura. Brought to you by our special community contributor @thomasrahm
        We generated a special version of Cura 5.2 called 5.3.0 Alpha + Xmas. The only changes we introduced compared to UltiMaker Cura 5.2.1 are those which are needed for the new supports. So keep in mind, this is not a sneak peek for Cura 5.3 (there are some really cool new features coming up) but a spotlight release highlighting this new version of tree supports.  
          • Like
        • 17 replies
      • New here? Get ahead with a free onboarding course
        Often getting started is the most difficult part of any process. A good start sets you up for success and saves you time and energy that could be spent elsewhere. That is why we have a onboarding course ready for
        Ultimaker S5 Pro Bundle, Ultimaker S5, Ultimaker S3 Ultimaker 2+ Connect.   
        They're ready for you on the Ultimaker Academy platform. All you need to do to gain access is to register your product to gain free access. 
        Ready? Register your product here in just 60 seconds.
          • Like
        • 14 replies
    • Create New...