diff --git a/fhem/FHEM/31_HUEDevice.pm b/fhem/FHEM/31_HUEDevice.pm
index c09b51215..590117370 100644
--- a/fhem/FHEM/31_HUEDevice.pm
+++ b/fhem/FHEM/31_HUEDevice.pm
@@ -752,7 +752,7 @@ HUEDevice_Parse($$)
     {
       $s = 'off';
       $percent = 0;
-      if( $on && $on != $hash->{helper}{on} ) {readingsBulkUpdate($hash,"onoff",0);}
+      if( defined($on) && $on != $hash->{helper}{on} ) {readingsBulkUpdate($hash,"onoff",0);}
     }
 
   if( $percent != $hash->{helper}{percent} ) {readingsBulkUpdate($hash,"level", $percent . ' %');}