diff --git a/Source/FieldSolver/ImplicitSolvers/WarpXSolverVec.H b/Source/FieldSolver/ImplicitSolvers/WarpXSolverVec.H
index ca8608bf557..edadfa21126 100644
--- a/Source/FieldSolver/ImplicitSolvers/WarpXSolverVec.H
+++ b/Source/FieldSolver/ImplicitSolvers/WarpXSolverVec.H
@@ -65,7 +65,7 @@ public:
 
     [[nodiscard]] inline bool IsDefined () const { return m_is_defined; }
 
-    void Define ( WarpX*     a_WarpX,
+    void Define ( WarpX*  a_WarpX,
                   warpx::fields::FieldType  a_array_type,
                   warpx::fields::FieldType  a_scalar_type = warpx::fields::FieldType::None );
 
@@ -282,8 +282,10 @@ public:
 private:
 
     bool m_is_defined = false;
+
     amrex::Vector<std::array<std::unique_ptr<amrex::MultiFab>,3>> m_array_vec;
     amrex::Vector<std::unique_ptr<amrex::MultiFab>> m_scalar_vec;
+
     warpx::fields::FieldType m_array_type = warpx::fields::FieldType::None;
     warpx::fields::FieldType m_scalar_type = warpx::fields::FieldType::None;
 
diff --git a/Source/FieldSolver/ImplicitSolvers/WarpXSolverVec.cpp b/Source/FieldSolver/ImplicitSolvers/WarpXSolverVec.cpp
index 61b67701da0..f2a88d82d42 100644
--- a/Source/FieldSolver/ImplicitSolvers/WarpXSolverVec.cpp
+++ b/Source/FieldSolver/ImplicitSolvers/WarpXSolverVec.cpp
@@ -66,6 +66,11 @@ void WarpXSolverVec::Define ( WarpX*     a_WarpX,
 
     }
 
+    WARPX_ALWAYS_ASSERT_WITH_MESSAGE(
+        m_array_type != FieldType::None ||
+        m_scalar_type != FieldType::None,
+        "WarpXSolverVec cannot be defined with both array and scalar vecs FieldType::None");
+
     m_is_defined = true;
 }