diff --git a/dumux/linear/amgbackend.hh b/dumux/linear/amgbackend.hh
index 5605fcd0c17db532e770b4efa64b95a76d5152f5..01cf1e44cfeecac72270e7f667be137409605158 100644
--- a/dumux/linear/amgbackend.hh
+++ b/dumux/linear/amgbackend.hh
@@ -98,7 +98,7 @@ public:
     AMGBackend(const GridView& gridView, const DofMapper& dofMapper)
     : gridView_(gridView)
     , dofMapper_(dofMapper)
-    , phelper_(gridView, mapper)
+    , phelper_(gridView, dofMapper)
     , firstCall_(true)
     {}