Is Form_Gestion_Intervenants a run object? onchange doesn't seem to be triggered for this kind of object. Therefore we need to place the code somewhere else (maybe in the form's custom code field)
Another thing to check in the meantime. If you paste and execute this code in the developer console (F12), will you get a value back?
Code: Select all
$("#Form_Gestion_Intervenants").contents().find("#Ref_Tiers_Intervenants").val()