Press the button right next to the brake pressure gauge (on the right). It says something like HL Fill or something similar.
I had a similar problem and the HLL button didn't work - I gave up after 10 mins of pressing everything, turning the train off and on again, all the usual stuff! The brake pipe stubbornly remained empty!
I tried it on my livestream... the throtte and brakes must be set to 0 for it to work, but the button does work.
Bonjour à tous, Lors d’un arrêt d’urgence causé par un excès de vitesse sous LZB, je ne peux pas recommencer, le pire tous les écrans coupés comme une panne de courant et impossible de recommencer arrivent sur le scénario Ice Breaker et (celui où vous commencez avec un 403 pour finir avec un 401) vous remerciant à l’avance. Cordialement, tof
There is a further thing to know when you train is stuck with the brakes. When you set the reverser, for whatever reason, to 0 and did not pressed the "Cab change" button on the rear wall, you will get an open "Knorr's big hole" on the brake pipe too. To get it back working, press the cab change button (lits up), put reverser in, set to M or V, brake key to on, press HLL fill and wait for the brake pipe to being filled over 2.8 BAR at least, press the cab change button again (it was reset by moving the reverser to M or V), reverser to 0 and wait for the displays going off, remove reverser, brake key to off. Now it's safe to change the cab. Right, even that is not covered in the tutorials, what is a shame at least. Tutorials were made before these system were implemented. A thing that needs improvement for sure.
Sorry to answer so late, a big thank you for the info, wouldn't there be a class 401 user guide explaining this or another doc to your knowledge please ??? Sincerely, tof