diff --git a/definitions/grib2/post_meta_data.hook.products_12.def b/definitions/grib2/post_meta_data.hook.products_12.def
index e22d01852..d7ad4e586 100644
--- a/definitions/grib2/post_meta_data.hook.products_12.def
+++ b/definitions/grib2/post_meta_data.hook.products_12.def
@@ -5,5 +5,10 @@
 concept gridSpecification(unknown, "gridSpecificationConcept.def", conceptsDir2, conceptsDir1): no_copy, read_only, dump;
 concept destineOrigin(unknown, "destineOriginConcept.def", conceptsDir2, conceptsDir1): no_copy, dump;
 
-# DestinE data does not have the domain key
+# ECC-1794: DestinE data does not have the domain key
 unalias mars.domain;
+
+# ECC-1796: stepRange indexing for DestinE ExtremesDT and On-Demand ExtremesDT data
+if (!(dataset is "climate-dt")) {
+    alias mars.step=stepRange;
+}
diff --git a/tests/grib_ecc-1691.sh b/tests/grib_ecc-1691.sh
index 97c38108d..bb0cb6d62 100755
--- a/tests/grib_ecc-1691.sh
+++ b/tests/grib_ecc-1691.sh
@@ -64,11 +64,12 @@ ${tools_dir}/grib_set -s numberOfDataPoints=12582912,gridDefinitionTemplateNumbe
 
 grib_check_key_equals $temp_grib_a "gridSpecification" "H1024"
 
-# Now check streams.
+# Now check streams for use in climate-dt.
 # Setting stream clte and type fc should set mars.date and mars.time to dataDate and dataTime,
 # and mars.step should be unaliased
+# We must also set dataset=climate-dt, since in other datasets mars.step is set to stepRange
 
-${tools_dir}/grib_set -s stream=clte,type=fc $destine_sample $temp_grib_a
+${tools_dir}/grib_set -s dataset=climate-dt,stream=clte,type=fc $destine_sample $temp_grib_a
 
 result1=$( ${tools_dir}/grib_get -p mars.date,mars.time $temp_grib_a )
 result2=$( ${tools_dir}/grib_get -p dataDate,dataTime $temp_grib_a )
@@ -79,8 +80,9 @@ ${tools_dir}/grib_ls -jm $temp_grib_a
 
 # Setting stream clmn and type fc should set mars.year and mars.month to year and month,
 # and mars.date, mars.time, mars.step should be unaliased
+# We must also set dataset=climate-dt, since in other datasets mars.step is set to stepRange
 
-${tools_dir}/grib_set -s stream=clmn,type=fc $destine_sample $temp_grib_a
+${tools_dir}/grib_set -s dataset=climate-dt,stream=clmn,type=fc $destine_sample $temp_grib_a
 
 result1=$( ${tools_dir}/grib_get -p mars.year,mars.month $temp_grib_a )
 result2=$( ${tools_dir}/grib_get -p year,month $temp_grib_a )