diff --git a/preprocessor/ModFile.cc b/preprocessor/ModFile.cc
index bba448ba616cd92c0dcedf8bb5c7f41deb40c90d..2f3ee4463ca3ee6e6e62e763bf9869bf342b258e 100644
--- a/preprocessor/ModFile.cc
+++ b/preprocessor/ModFile.cc
@@ -289,7 +289,7 @@ ModFile::checkPass()
 
   // Check if some exogenous is not used in the model block
   set<int> unusedExo = dynamic_model.findUnusedExogenous();
-  if (unusedExo.size() > 1)
+  if (unusedExo.size() > 0)
     {
       warnings << "WARNING: some exogenous (";
       for (set<int>::const_iterator it = unusedExo.begin();