HMS 0300-1800-0001-0006: heatbed levelling data abnormal
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The levelling routine produced a height map the firmware will not accept. The usual cause is something physically on the plate or on the nozzle tip, not a bent bed. Clean both and run it again.
Affected machines: A2L, H2, P2S. The machine probes the bed at a grid of points and builds a compensation map. This code means the resulting map failed a sanity check.
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One high point corrupts the whole map
The probe measures the gap between the nozzle and the plate. It cannot distinguish a genuinely high bed from a chip of filament sitting on the plate or a blob stuck to the nozzle tip. Either one enters the map as real geometry.
That matters more than it sounds, because compensation is applied across the whole surface. A single false high point does not just ruin one spot; it tilts the interpolation around it and puts the nozzle wrong over a wide area.
Levelling sequence completes but the machine rejects the result, or the code appears at the start of a print
Debris on the plate or nozzle tip, or an obstruction on the Z slider
- Power off, remove the build plate and wash it in hot water with dish soap, then dry it fully. Alcohol removes oil but not the polymer film that builds up.
- Inspect the nozzle tip with the hotend warm and remove any bead of hardened filament with tweezers.
- Check the Z sliders for debris, since a sticky axis produces inconsistent probe heights.
- Refit the plate and make sure it sits fully home with nothing trapped underneath it.
- Run the levelling routine again and let it store a fresh map.
If a clean plate and a clean nozzle still produce a rejected map, the bed may genuinely be out of flat. That is a hardware matter rather than a cleaning one, and a warped plate will show as a consistent pattern rather than a single outlier.
Our page on bed levelling and mesh compensation explains what the map is doing and how far compensation can actually correct. If the visible symptom is a first layer that will not stick, first layer adhesion covers that directly, and the troubleshooting index covers the rest.
FAQ
Do I need a new plate? Usually not. Wash it properly before concluding it is worn.
Why does the nozzle tip matter? The probe measures the gap from the tip, so a blob on it reads as a high bed.
Is alcohol enough to clean the plate? For oil, yes. For the built-up film, you need soap and hot water.
Can a warped plate cause this? Yes, but it shows as a consistent pattern rather than one bad point.
LayerWalker
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