@gilou
Your issue is being caused by the fact that you are using entity selectors to define a target. You can either change to a Target selector and keep the actions as they are, or keep the entity selectors and modify your actions:
action:
- alias: "Allume l'electronvanne"
service: switch.turn_on
target:
entity_id: !input switchEV
- alias: "lance le timer"
service: timer.start
data:
duration: "00:{{ timeDuration }}:00"
target:
entity_id: !input timerEV
@Kszys
Post the automation/blueprint you are using.