diff --git a/tests/grib_secondary_bitmap.sh b/tests/grib_secondary_bitmap.sh
index 11af77e6b..05cfb5951 100755
--- a/tests/grib_secondary_bitmap.sh
+++ b/tests/grib_secondary_bitmap.sh
@@ -18,6 +18,7 @@ tempLog=temp.$label.log
 tempRef=temp.$label.ref
 
 # Use a GRIB2 input with a bitmap
+# ----------------------------------
 input=$data_dir/reduced_latlon_surface.grib2
 grib_check_key_equals $input bitmapPresent 1
 ${tools_dir}/grib_set -s packingType=grid_simple_matrix,NC=1,NR=1 $input $tempGribA
@@ -26,10 +27,23 @@ ${tools_dir}/grib_dump -O $tempGribB
 ${tools_dir}/grib_dump -Dat $tempGribB
 
 # Call pack_double and unpack_double
+# ----------------------------------
 cat >$tempFilt<<EOF
   set values = {0, 1, 9999};
   print "[bitmap]";
 EOF
 ${tools_dir}/grib_filter $tempFilt $tempGribB
 
+# data_g1secondary_bitmap
+# ----------------------------------
+cat >$tempFilt<<EOF
+  transient expandBy = 1;
+  meta _s data_g1secondary_bitmap(bitmap,secondaryBitmaps,missingValue,expandBy,octetAtWichPackedDataBegins);
+  print "[_s]";
+  set _s = {0, 9};
+EOF
+# The above filter is for testing only. Add -f as we know it will fail
+${tools_dir}/grib_filter -f $tempFilt $tempGribB
+
+# Clean up
 rm -f $tempGribA $tempGribB $tempFilt $tempLog $tempRef