What happened?
The Modular Bed Control Unit (MCU) monitors temperature to ensure the printer operates within safe limits. When the internal temperature exceeds a defined threshold, the printer displays a warning "Microcontroller unit of %s is overheating", where in place of %s, the name of the component is shown.
Error name: MCU Overheat
Error code: #35270
How to fix it?
This warning typically appears when the ambient temperature around the printer is too high, or when the printer is enclosed without proper ventilation.
- Ensure the printer is used in an environment with ambient temperature below 30 °C (86 °F).
- Allow the printer to cool down: turn it off and let it rest for at least 10–15 minutes before continuing.
- Minimize continuous long-duration prints at high bed temperatures, especially in warm environments.
If the issue persists even in a cool environment, contact our Support for further diagnostics, as the internal sensors or electronics may be faulty.
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1 comment
Its not that the temp is too high, its that the componentry is not tolerating what amounts to standard, within-specification conditions.
The Heated bed specification says the bed can tolerate up to 115C, and some materials like ASA require 110C bed temp and the prints may be of long direction: this is after all an XL printer, able to accommodate large models, and they take a long time to print. Its completely unacceptable for the printer to complain of overtemp error, the components need to be higher rated !!!
If it needs a fan to achieve the specification, why then is that fan not already inbuilt, and why do I need to go out and adopt a 3RD party solution ?
The cost of the High temp version (STM32G071RBT3) of the MCU Board with 125C heat tolerance is $1.50 more than the sTM3232GO70R BT6 used on the board. And its a drop in replacement. Why not used ???