diff --git a/fhem/CHANGED b/fhem/CHANGED
index 50020eaab..4d8f88544 100644
--- a/fhem/CHANGED
+++ b/fhem/CHANGED
@@ -1,5 +1,6 @@
 # Add changes at the top of the list. Keep it in ASCII, and 80-char wide.
 # Do not insert empty lines here, update check depends on it.
+  - bugfix:  14_CUL_TCM97001: Fix checksum calculation for GT_WT_02
   - change:  10_IT: Implementation for HE800 de-/encoding
                     Implementation for HE800 dimmer
                     Fix wrong return values
diff --git a/fhem/FHEM/14_CUL_TCM97001.pm b/fhem/FHEM/14_CUL_TCM97001.pm
index d2f4bd6fa..4025bdd10 100755
--- a/fhem/FHEM/14_CUL_TCM97001.pm
+++ b/fhem/FHEM/14_CUL_TCM97001.pm
@@ -202,9 +202,10 @@ sub checkCRC_Mebus {
 sub checkCRC_GTWT02 {
   my $msg = shift;
   my @a = split("", $msg);
-
   my $CRC = (hex($a[0])+hex($a[1])+hex($a[2])+hex($a[3])
-            +hex($a[4])+hex($a[5])+hex($a[6])+hex($a[7])) -1;
+            +hex($a[4])+hex($a[5])+hex($a[6])+(hex($a[7]) & 0xE));
+#  my $CRC = (hex($a[0])+hex($a[1])+hex($a[2])+hex($a[3])
+#            +hex($a[4])+hex($a[5])+hex($a[6])+hex($a[7])) -1;
   my $CRCCHECKVAL= (hex($a[7].$a[8].$a[9]) & 0x1F8) >> 3; 
   if ($CRC == $CRCCHECKVAL) {
       return TRUE;
@@ -1247,6 +1248,8 @@ CUL_TCM97001_Parse($$)
 
 
 =pod
+=item summary    This module interprets temperature sensor messages.
+=item summary_DE Module verarbeitet empfangene Nachrichten von Temp-Sensoren.
 =begin html
 
 <a name="CUL_TCM97001"></a>