diff --git a/DDG4/python/DDSim/DD4hepSimulation.py b/DDG4/python/DDSim/DD4hepSimulation.py
index 1ccfa0cf49f13d9f8e8323c69188418f850eb61d..81b064ad4f94b0bd3dfd9c2a9837cfeeb6e4d1fd 100644
--- a/DDG4/python/DDSim/DD4hepSimulation.py
+++ b/DDG4/python/DDSim/DD4hepSimulation.py
@@ -592,7 +592,7 @@ class DD4hepSimulation(object):
           logger.info('       replace default action with : %s', action)
           break
       if abortForMissingAction and action is None:
-        logger.error('Cannot find Action for detector %s. Extend "action.mapAction"', det)
+        logger.error('Cannot find Action for detector %s. You have to extend "action.mapAction"', det)
         raise RuntimeError("Cannot find Action")
       seq, act = setupFuction(det, type=action)
       self.filter.applyFilters(seq, det, defaultFilter)
diff --git a/DDG4/python/DDSim/Helper/Action.py b/DDG4/python/DDSim/Helper/Action.py
index e7726548335f0cb4e5dec1bb36113c6aa2c694a8..b046d3c3eda8faf7cb5f77f697d5e31d1b0cfa19 100644
--- a/DDG4/python/DDSim/Helper/Action.py
+++ b/DDG4/python/DDSim/Helper/Action.py
@@ -65,7 +65,7 @@ class Action(ConfigHelper):
   def mapActions(self):
     """Create a map of patterns and actions to be applied to sensitive detectors.
 
-    Example: if the name of the detector matches tpc the TPCSDAction is used.
+    Example: if the name of the detector matches 'tpc' the TPCSDAction is used.
 
       SIM.action.mapActions['tpc'] = "TPCSDAction"
     """