The Motor Does Not Work in the ESU Profi Test Stand

I connected the track input of the ESU Profi Test Stand 53900 to the motor output of a CTC locomotive module configured for DCC. Now, when I plug my Piko SmartDecoder 4.1 into the ESU Profi Test Stand, I can turn the light on and off via the CTC app, but the motor does not work.

This seems to be an incompatibility between the ESU Profi Test Stand 53900 and some decoders, see the article in the Stummi forum.