diff --git a/Marlin/pins.h b/Marlin/pins.h
index f841cd71290fb47b7c67da745e7cb36a5f2d9e4a..6d97df2ac1f14397fbe20307f77a467dd9bdac6b 100644
--- a/Marlin/pins.h
+++ b/Marlin/pins.h
@@ -219,6 +219,7 @@
 #endif
 
 #if ENABLED(DISABLE_YMAX_ENDSTOP)
+  #undef Y_MAX_PIN
   #define Y_MAX_PIN          -1
 #endif