There is a problem with one of the thermistors, printer will not allow you to print until issue is resolved and printer is restarted.
Indication: MINTEMP is shown on the LCD screen and at-least one of the temperature readouts show below 16°C.
- Thermistor is not plugged in correctly to the RAMBo mini board. Check if the connector is fully plugged into the board on the right place. (obrazek z manualu). Check if the crimped contacts on the leads are fully inserted into the connector housing, if not, push them fully inside until secured and replug the connector.
- Thermistor leads are broken. Can be simply verified by multimeter, if it fails to read the resistance (infinite resistance), the leads are broken. Can happen only during assembly as all hotends are prebuilt and tested on our test bench. Replacement is needed. (Semitec 100kOhm NTC Thermistor. 104GT-2)
- RAMBo mini thermistor input is broken. Highly unlikely, the board would fail to pass the final testing on our test bench. If only one temperature readout shows 0C. Try switching the Hotend and Heatbed thermistors, if the faulty readout remains the same, the RAMBo is broken. The problem can happen is 12+ volts are connected to the input during assembly. New RAMBo is needed.
- Ambient temperature is below 16°C. It is not a good idea to print in temperatures that low. However, there is a workaround. Heat the printer hotend and heatbed with hair drier, reset and start preheating. Minimum temperature check can't by disabled by user for safety reasons.