MAXTEMP ERROR
Creality 3D Printer
Severity: CriticalWhat Does This Error Mean?
MAXTEMP ERROR means the printer is reading a temperature above the maximum safe threshold (usually 275-300°C for the hotend). This could mean the thermistor is shorted, giving a false high reading, or the heater is actually overheating. Check the thermistor wiring for short circuits.
Affected Models
- Creality Ender 3
- Creality Ender 3 V2
- Creality Ender 5
- Creality CR-10
- All Marlin-based printers
Common Causes
- Thermistor wires shorted together
- Thermistor wires touching the heater block (metal contact)
- Actual overheating due to PID tuning failure
- Wrong thermistor type set in firmware
- Mainboard analog input fault
How to Fix It
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Check the thermistor wires for short circuits.
If the two thermistor wires touch each other or touch the metal heater block, the reading goes extremely high. Separate the wires and insulate with heat-resistant tape.
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Make sure the thermistor is properly insulated from the heater block.
The thermistor should be held in by a screw but should not have bare wires touching metal. Use a small piece of thermal tape or Kapton tape to insulate.
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Check if the actual temperature is high or if it is a false reading.
If the hotend is cold to the touch but the display shows 300°C, it is a wiring/sensor issue. If it is actually hot, the heater may be stuck on — unplug the printer immediately.
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Replace the thermistor if the wires are damaged.
A thermistor with frayed or damaged insulation will keep causing shorts. Replace it with a new NTC 100K thermistor ($2-$5).
Frequently Asked Questions
Is MAXTEMP a fire risk?
MAXTEMP itself is the safety system catching the problem. But if the heater is actually running away, yes — that is a fire risk. The MAXTEMP error stops the heater to prevent this.
What is the maximum safe temperature for an Ender 3 hotend?
The stock Ender 3 hotend with PTFE tube lining should not exceed 240°C. All-metal hotend upgrades can safely reach 285-300°C.