3 sourced reports, with what to check before you buy. Each one links to the page it was reported on.
Costly or dangerous
Dyson identifies the printed circuit board short as the defect and installs a protective part
Dyson's Japanese notice names the concrete part: an electrical short on the printed circuit board, fixed by fitting a protective board component.
What to check. The defect is on the PCB; the recall remedy is a free engineering fix (protective part) or replacement, so an affected unit should not be used until fixed.
Owner reports AM05 overheated, tripped circuit breaker and blew out wall socket
A verified-buyer review on a retailer site reports a real overheating incident: burning smell, tripped breaker, blown wall socket after the second use.
What to check. This is an owner-reported incident consistent with the documented short-circuit hazard; treat any burning smell or tripped breaker as a reason to stop using and unplug the unit immediately.
These reports come from the pages linked under each item: owner forums, repair guides and workshops. They are not a diagnosis of any one unit, and a careful check of the one you are buying still applies.
Text from the Kriko Electric space heaters catalog, version 0.1.1, under the CC-BY-SA-4.0 license.