diff --git a/src/octoprint/static/js/app/viewmodels/terminal.js b/src/octoprint/static/js/app/viewmodels/terminal.js
index 9636e860..b524afcc 100644
--- a/src/octoprint/static/js/app/viewmodels/terminal.js
+++ b/src/octoprint/static/js/app/viewmodels/terminal.js
@@ -272,7 +272,7 @@ $(function() {
         };
 
         self.fakeAck = function() {
-            OctoPrint.printer.fakeAck();
+            OctoPrint.connection.fakeAck();
         };
 
         self.handleKeyDown = function(event) {