diff --git a/sources/telemac3d/condim.f b/sources/telemac3d/condim.f
index 36b59255633026a3ff85a13c0d6a9ba9922bfaf3..58b76c676e7c54ebacee440139fcf6c53362ccd0 100644
--- a/sources/telemac3d/condim.f
+++ b/sources/telemac3d/condim.f
@@ -252,7 +252,7 @@
           CALL PLANTE(1)
         ENDIF
       ENDDO
-      DO I=1,NPLAN-1
+      DO I=2,NPLAN-2
         IF((TRANSF_PLANE%I(I).EQ.3.AND.TRANSF_PLANE%I(I+1).EQ.3)
      &  .AND.ZPLANE%R(I+1).LE.ZPLANE%R(I)) THEN
           WRITE(LU,*) 'Z COORDINATE (ZPLANE) DOES NOT INCREASE ',