diff --git a/typo3/sysext/backend/Resources/Public/JavaScript/FormEngineValidation.js b/typo3/sysext/backend/Resources/Public/JavaScript/FormEngineValidation.js
index 76b911bcd01ecf67835a614cf7f2753cbb869b8d..10b842d415537b2e670b6d7f74c21828f3080ec6 100644
--- a/typo3/sysext/backend/Resources/Public/JavaScript/FormEngineValidation.js
+++ b/typo3/sysext/backend/Resources/Public/JavaScript/FormEngineValidation.js
@@ -66,7 +66,6 @@ define([
     FormEngineValidation.lastYear = FormEngineValidation.getYear(today);
     FormEngineValidation.lastDate = FormEngineValidation.getDate(today);
     FormEngineValidation.lastTime = 0;
-    FormEngineValidation.USmode = 0;
     FormEngineValidation.validate();
   };
 
diff --git a/typo3/sysext/backend/Tests/JavaScript/FormEngineValidationTest.js b/typo3/sysext/backend/Tests/JavaScript/FormEngineValidationTest.js
index aa925317e77b4376d4dcae2cda2d1e1ac9e19307..97731bebbb938c9422c9069a8d4c044a1e240149 100644
--- a/typo3/sysext/backend/Tests/JavaScript/FormEngineValidationTest.js
+++ b/typo3/sysext/backend/Tests/JavaScript/FormEngineValidationTest.js
@@ -93,6 +93,7 @@ define(['jquery', 'TYPO3/CMS/Backend/FormEngineValidation'], function($, FormEng
       using(formatValueDataProvider, function(testCase) {
         it(testCase.description, function() {
           FormEngineValidation.USmode = 0;
+          FormEngineValidation.initialize();
           var result = FormEngineValidation.formatValue(testCase.type, testCase.value, testCase.config);
           expect(result).toBe(testCase.result);
         });
@@ -155,6 +156,7 @@ define(['jquery', 'TYPO3/CMS/Backend/FormEngineValidation'], function($, FormEng
       using(formatValueUsModeDataProvider, function(testCase) {
         it(testCase.description, function() {
           FormEngineValidation.USmode = 1;
+          FormEngineValidation.initialize();
           var result = FormEngineValidation.formatValue(testCase.type, testCase.value, testCase.config);
           expect(result).toBe(testCase.result);
         });