The Ender-5 covered here is the original 2019 cube-frame model, not the Ender-5 Pro, Ender-5 Plus, Ender-5 S1, or Ender-5 Max. Those later variants moved to 32-bit boards and, in the case of the S1 and Max, a color touchscreen running Creality’s own interface, which is where the numbered “Key: XXXX” fault codes documented on wiki.creality.com and used in this site’s Ender-3 V3 Plus, Ender-3 V3 KE, SparkX i7, and K1C guides come from. The base Ender-5 shipped with an 8-bit control board and a monochrome 12864 LCD, and it runs firmware that is essentially stock Marlin with Creality’s menu labels. Creality’s own Ender-5 Guide Book (V.1.0) includes a “Trouble shooting” heading on page 15 of the printed manual, but the page itself carries no readable troubleshooting text in either the manualslib mirror or the PDF pulled directly from Creality’s own distribution copy, just the section title and a page number. There is no numbered error table anywhere in that document, and no dedicated Ender-5 (non-Plus, non-Pro, non-Max, non-S1) page exists on wiki.creality.com with fault codes either. Because of that gap, the messages below come from Marlin’s own documented halt and error conditions, the same firmware base the Ender-5 runs, cross-checked against user reports of what actually shows up on the Ender-5’s screen.
Heating and thermal faults
The most common thing an Ender-5 owner will see on the LCD when something goes wrong with temperature control is MINTEMP or MAXTEMP, printed with the axis or heater identifier (for example the hotend or the bed). This fires when the thermistor reading falls below or rises above the sane range Marlin expects, which almost always means a broken or shorted thermistor wire, a thermistor that has pulled loose from the nozzle block, or (for MAXTEMP) a heater cartridge that is stuck on. The fix starts with checking the thermistor connector at the hotend and at the board, since flexing during printing is the usual failure point on this printer’s factory wiring harness.
Heating failed appears when the nozzle or bed temperature rises too slowly while still below its target. Marlin watches the rate of climb, not just the final number, so a heater that is technically working but underpowered, a loose heater cartridge connection, or a partially seated thermistor can all trigger this even though the part eventually reaches temperature on a bench test. Thermal runaway is the related but more serious message: the temperature has drifted too far from the target for too long after the heater already settled near it. On an Ender-5 this is worth checking against airflow first, since a part-cooling fan blowing across the hotend heat block is a known cause of false thermal runaway trips on this generation of Creality hotend, separate from any actual electrical fault. Both conditions halt the print and require a full power cycle to clear, since Marlin will not resume a heater it has already flagged as unsafe.
Homing and leveling faults
The stock Ender-5 uses mechanical endstop switches on X, Y, and Z, and bed leveling is manual, done with the four thumbscrews under the platform rather than any auto-leveling probe. There is no BLTouch or CR Touch included with the base model, so the Marlin messages tied to G29 auto bed leveling (“probing failed” and similar) do not apply here unless an owner has added a probe as an aftermarket modification. What does show up on the stock machine is a generic homing failure: the printer will refuse to complete Auto Home and the screen will report the axis stalling or failing to reach its endstop, most often because an endstop switch has come loose in its mount, a cable has pulled free at the connector, or the switch itself has failed. Because the base Ender-5’s firmware and screen give little detail beyond that generic failure, diagnosis is manual: check continuity at the affected switch, confirm the cable didn’t get pinched during a Z-axis rebuild, and swap the suspect switch with a known-good one from another axis if the fault follows the connector rather than the position.
Firmware and EEPROM faults
After a firmware reflash, or occasionally after a power loss mid-write, Marlin can report EEPROM CRC mismatch or Error: EEPROM datasize error on boot. This happens when the settings block stored in EEPROM no longer matches the layout the current firmware expects, which is common after jumping between firmware versions with different feature sets compiled in. The documented fix is to send M502 to load the compiled-in defaults, then M500 to write them back to EEPROM, and reboot. If the same error keeps appearing after that, it points to a genuine mismatch bug in the firmware build rather than a one-off corruption, and the practical answer on an 8-bit board like the Ender-5’s is usually to reflash with a firmware build matched specifically to that mainboard revision.
Filament and extrusion notes
Because the stock board has no dedicated filament runout sensor port, the base Ender-5 does not show a runout prompt out of the box the way later Creality printers do. Owners who add a runout sensor through an aftermarket adapter will get Marlin’s standard filament change prompt when the sensor triggers, but that is a modification, not documented factory behavior. Extrusion problems on the stock machine (clicking extruder, under-extrusion, clogs) do not generate a distinct on-screen message at all; the printer will keep running the print job with no filament moving, since there is no flow sensor to detect it. That’s a real limitation of this printer generation worth knowing before assuming the screen will warn you about a clog.