Forgot to update the post, managed to talk to a hyster tech which sent me some shcematics.
I did check the relay and it's ok(really annoying you have to take out th entire airbox to access the relay and even then it's not very accesible), bench tested it outside the elevator.
The control line has 8V open circuit when the machine goes in contact.
With the relay plugged it's always 0v.

I want to measure the wire coming out from the ECU, but for that i need a photo/reference of which connector/pin is the one that has the relay line, because otherwise it's quite impossible to trace