diff --git a/DDTest/CMakeLists.txt b/DDTest/CMakeLists.txt
index cd6d85c4c7497242bc9d7e72ac601603d1d26ed0..ac51cb3196ed07d7b4d6cd613a98bf072b37552d 100644
--- a/DDTest/CMakeLists.txt
+++ b/DDTest/CMakeLists.txt
@@ -64,7 +64,7 @@ if (DD4HEP_USE_GEANT4)
 
   ADD_TEST( t_test_ddsim "${CMAKE_INSTALL_PREFIX}/bin/run_test.sh"
     ddsim --compactFile=${CMAKE_INSTALL_PREFIX}/DDDetectors/compact/SiD.xml --runType=batch -G -N=2 --outputFile=testSid.root
-    --part.userParticleHandler=)
+    --gun.position "0.0 0.0 0.0" --gun.direction "1.0 0.0 1.0" --gun.energy 100*GeV --part.userParticleHandler=)
   SET_TESTS_PROPERTIES( t_test_ddsim PROPERTIES FAIL_REGULAR_EXPRESSION  "Exception;EXCEPTION;ERROR;Error" )
 
 endif()