Prusa 3D Printer Error Code 1: How to Fix It

Q: What does MINTEMP bed mean on a Prusa printer?

MINTEMP bed means the printer's firmware detected a temperature reading from the heated bed thermistor that is below the minimum expected value. This usually signals a broken, disconnected, or shorted thermistor — it does not necessarily mean the bed is actually cold, but rather that the temperature sensor is not reporting a valid value.

Q: Can I keep printing if I get Error Code 1 on my Prusa?

No. Error Code 1 halts the printer as a safety measure. Without a working bed thermistor, the firmware cannot monitor or safely regulate bed temperature, which could lead to overheating, fire, or damage to the printer. You must resolve the error before printing again.

Q: How do I know if my Prusa bed thermistor is broken?

Use a multimeter set to resistance (Ohms) mode. Disconnect the thermistor from the board and probe its two wires. At room temperature, a healthy NTC 100k thermistor reads approximately 100,000 Ohms. A reading of 0 or infinite/OL means the thermistor is faulty and needs replacing.

Q: Which thermistor do I need to replace the bed thermistor on my Prusa?

Most Prusa printers (MK2, MK3, MK3S, MK4, MINI, MINI+) use a standard NTC 100k thermistor for the heated bed. Always verify with Prusa's official documentation or spare parts store for your specific model to ensure compatibility, as connector types and wire lengths can vary.

Q: Why does my Prusa show Error Code 1 only sometimes and not every time?

An intermittent Error Code 1 usually points to a partially broken or fraying thermistor wire, or a loose connector that loses contact with vibration during printing. Flex the thermistor cable gently while monitoring the temperature reading — if the value jumps or drops erratically, you have found a break in the wire. Replace the thermistor and ensure the cable is routed without tight bends or pinch points.

Abstract

Prusa Error Code 1 is a MINTEMP bed error, meaning the printer's firmware has detected that the heated bed temperature is reading abnormally low — often below the minimum safe threshold. This is almost always caused by a faulty, disconnected, or damaged bed thermistor (the small temperature sensor attached to the heated bed). Until the error is resolved, the printer will refuse to heat the bed or start a print job to prevent damage or a fire hazard.