diff --git a/dafoam/pyDAFoam.py b/dafoam/pyDAFoam.py
index 84b337f0..a712a75b 100755
--- a/dafoam/pyDAFoam.py
+++ b/dafoam/pyDAFoam.py
@@ -2071,7 +2071,7 @@ def calcTotalDerivsFFD(self, objFuncName, designVarName, dFScaling=1.0, accumula
             if designVarName in self.getOption("writeSensMap"):
                 dFdXs = self.mesh.getdXs()
                 dFdXs = self.mapVector(dFdXs, self.allWallsGroup, self.designSurfacesGroup)
-                Xs = self.getSurfaceCoordinates(self.allWallsGroup)
+                Xs = self.getSurfaceCoordinates(self.designSurfacesGroup)
                 dFdXsFlatten = dFdXs.flatten()
                 XsFlatten = Xs.flatten()
                 size = len(dFdXsFlatten)