diff --git a/src/components/time-control.vue b/src/components/time-control.vue
index a4c20f2..4e338e8 100644
--- a/src/components/time-control.vue
+++ b/src/components/time-control.vue
@@ -142,7 +142,7 @@ export default {
       );
     },
     updateTimeValue(v) {
-      this.updateValue(this.dateValue, v);
+      this.updateValue(null, v);
     },
     updateValue(theDate, theTime) {
       const vm = this;