diff --git a/octoprint_enclosure/templates/enclosure_tab.jinja2 b/octoprint_enclosure/templates/enclosure_tab.jinja2
index bda754b..4ff6d61 100644
--- a/octoprint_enclosure/templates/enclosure_tab.jinja2
+++ b/octoprint_enclosure/templates/enclosure_tab.jinja2
@@ -34,7 +34,7 @@
 </table>
 
 <h4><p data-bind="html: settings.settings.plugins.enclosure.io1Label"></p></h4>
-<button type="submit" data-bind="click: handleIO.bind($data, 'io1', 'on')" class="btn">Turn on</button> 
+<button type="submit" data-bind="click: handleIO.bind($data, ['io1', 'on'])" class="btn">Turn on</button> 
 <button type="submit" data-bind="click: handleIO.bind($data, 'io1', 'off'), enable: settings.settings.plugins.enclosure.io1Enable && isConnected()"   class="btn">Turn off</button>