Prusa XL Error Code 15: Probe Homing Failed – How to Fix It

Q: What causes Prusa XL Error Code 15?

Error Code 15 on the Prusa XL means the probe homing sequence failed. Common causes include a dirty nozzle tip preventing the load cell from detecting the bed correctly, a loose or damaged probe cable, an incorrect Z-probe offset value, outdated firmware, or a defective probe sensor. In most cases, cleaning the nozzle and re-running calibration resolves the issue.

Q: Can I keep printing if I get Error Code 15 on my Prusa XL?

No. You should not attempt to print while Error Code 15 is active. The homing failure means the printer cannot reliably determine the nozzle's position relative to the bed. Continuing to print risks the nozzle crashing into the print sheet or bed hardware, potentially causing damage to the nozzle, probe, print sheet, or heated bed surface.

Q: Does updating firmware fix Prusa XL Error Code 15?

In some cases, yes. Firmware bugs have occasionally caused probe homing errors on the Prusa XL, and Prusa regularly releases updates that address these issues. Always make sure you are running the latest stable firmware version. However, if the error is caused by a hardware issue like a damaged cable or faulty sensor, a firmware update alone will not resolve it.

Q: How do I re-calibrate the Z-probe on the Prusa XL after fixing Error Code 15?

After fixing the underlying issue, run the full calibration sequence from the printer's LCD menu. Go to Main Menu > Calibration > First Layer Calibration (the exact path may vary slightly by firmware version). Follow the on-screen instructions to set the correct live Z-offset. Prusa's official documentation at help.prusa3d.com provides a detailed step-by-step calibration guide specific to the XL model.

Q: Is Prusa XL Error Code 15 covered under warranty?

If your Prusa XL is within its warranty period and the probe failure is due to a manufacturing defect rather than user damage, it should be covered. Contact Prusa Research support through their official help portal at help.prusa3d.com with your order details and a description of the error. They typically respond quickly and can arrange replacement parts or guide you through advanced diagnostics under warranty.

Abstract

Prusa XL Error Code 15 indicates that the printer's probe failed to complete its homing sequence correctly. This typically means the Z-probe (SuperPINDA or load cell probe) could not detect the print bed during the homing routine, which can be caused by wiring issues, a dirty nozzle or probe tip, incorrect probe height, or a firmware/calibration problem. Resolving this error is important before printing, as an uncorrected homing failure can result in the nozzle crashing into the bed or producing failed prints.