Description:  While printing an object in Ultimaker 3D printer, suddenly the printer gets stopped and Error - STOPPED temp sensor bed message displayed. This error repeats even after the printer is shut down and restarted.

Action: The most likely reason for this issue is loose connection at the main board or damage to the sensor. Turn off the Ultimaker, disconnect the power supply and follow the below steps carefully. It is bit complicated to resolve the issue. So, please follow these steps carefully. Ultimaker motherboard is at the bottom of the machine. So, to check if there is a bad connection on the main board, you first have to take a look at the bottom of Ultimaker.

Step 1: Move the build plate up by hand so that you can better reach the screws in the bottom panel.

Step 2: Place Ultimaker on the right side so that you can access the bottom side

Step 3: You will find a big metal cover. Loosen the two screws with which it is attached to the bottom of the Ultimaker and remove the cover. You can do this by using a 2mm HEX wrench on the screws at the inside of Ultimaker and pliers to hold the lock nut at the other side.

Step 4: You will now see the main board. Look for the sensor cable, which is connected to 'TEMP1'

Step 5: Make sure the cable is connected to 'TEMP1'. Check if all the wires are properly inserted in the connector.