diff --git a/Marlin/Conditionals_post.h b/Marlin/Conditionals_post.h
index 09c16f352..978b6297b 100644
--- a/Marlin/Conditionals_post.h
+++ b/Marlin/Conditionals_post.h
@@ -413,9 +413,10 @@
     #endif
   #endif
 
-  #define IS_Z2_OR_PROBE(P) (   (PIN_EXISTS(Z2_MIN)      && (P) == Z2_MIN_PIN)       \
-                             || (PIN_EXISTS(Z2_MAX)      && (P) == Z2_MAX_PIN)       \
-                             || (PIN_EXISTS(Z_MIN_PROBE) && (P) == Z_MIN_PROBE_PIN))
+  // Is an endstop plug used for the Z2 endstop or the bed probe?
+  #define IS_Z2_OR_PROBE(A,M) ( \
+       (ENABLED(Z_DUAL_ENDSTOPS) && Z2_USE_ENDSTOP == _##A##M##_) \
+    || (ENABLED(Z_MIN_PROBE_ENDSTOP) && Z_MIN_PROBE_PIN == A##_##M##_PIN ) )
 
   /**
    * Set ENDSTOPPULLUPS for active endstop switches
@@ -505,12 +506,12 @@
   #define HAS_SOLENOID_4    (PIN_EXISTS(SOL4))
 
   // Endstops and bed probe
-  #define HAS_X_MIN (PIN_EXISTS(X_MIN) && !IS_Z2_OR_PROBE(X_MIN_PIN))
-  #define HAS_X_MAX (PIN_EXISTS(X_MAX) && !IS_Z2_OR_PROBE(X_MAX_PIN))
-  #define HAS_Y_MIN (PIN_EXISTS(Y_MIN) && !IS_Z2_OR_PROBE(Y_MIN_PIN))
-  #define HAS_Y_MAX (PIN_EXISTS(Y_MAX) && !IS_Z2_OR_PROBE(Y_MAX_PIN))
-  #define HAS_Z_MIN (PIN_EXISTS(Z_MIN) && !IS_Z2_OR_PROBE(Z_MIN_PIN))
-  #define HAS_Z_MAX (PIN_EXISTS(Z_MAX) && !IS_Z2_OR_PROBE(Z_MAX_PIN))
+  #define HAS_X_MIN (PIN_EXISTS(X_MIN) && !IS_Z2_OR_PROBE(X,MIN))
+  #define HAS_X_MAX (PIN_EXISTS(X_MAX) && !IS_Z2_OR_PROBE(X,MAX))
+  #define HAS_Y_MIN (PIN_EXISTS(Y_MIN) && !IS_Z2_OR_PROBE(Y,MIN))
+  #define HAS_Y_MAX (PIN_EXISTS(Y_MAX) && !IS_Z2_OR_PROBE(Y,MAX))
+  #define HAS_Z_MIN (PIN_EXISTS(Z_MIN) && !IS_Z2_OR_PROBE(Z,MIN))
+  #define HAS_Z_MAX (PIN_EXISTS(Z_MAX) && !IS_Z2_OR_PROBE(Z,MAX))
   #define HAS_Z2_MIN (PIN_EXISTS(Z2_MIN))
   #define HAS_Z2_MAX (PIN_EXISTS(Z2_MAX))
   #define HAS_Z_MIN_PROBE_PIN (PIN_EXISTS(Z_MIN_PROBE))
diff --git a/Marlin/SanityCheck.h b/Marlin/SanityCheck.h
index 07e4224e2..722d7f586 100644
--- a/Marlin/SanityCheck.h
+++ b/Marlin/SanityCheck.h
@@ -77,7 +77,7 @@
 #elif defined(DISABLE_MAX_ENDSTOPS) || defined(DISABLE_MIN_ENDSTOPS)
   #error "DISABLE_MAX_ENDSTOPS and DISABLE_MIN_ENDSTOPS deprecated. Use individual USE_*_PLUG options instead."
 #elif ENABLED(Z_DUAL_ENDSTOPS) && !defined(Z2_USE_ENDSTOP)
-  #error "Z_DUAL_ENDSTOPS settings are simplified. Just set Z2_USE_ENDSTOP to the endstop you want to repurpose for Z2"
+  #error "Z_DUAL_ENDSTOPS settings are simplified. Just set Z2_USE_ENDSTOP to the endstop you want to repurpose for Z2."
 #elif defined(LANGUAGE_INCLUDE)
   #error "LANGUAGE_INCLUDE has been replaced by LCD_LANGUAGE. Please update your configuration."
 #elif defined(EXTRUDER_OFFSET_X) || defined(EXTRUDER_OFFSET_Y)
@@ -916,6 +916,8 @@ static_assert(1 >= 0
 #elif ENABLED(Z_DUAL_ENDSTOPS)
   #if !Z2_USE_ENDSTOP
     #error "You must set Z2_USE_ENDSTOP with Z_DUAL_ENDSTOPS."
+  #elif Z2_MAX_PIN == 0 && Z2_MIN_PIN == 0
+    #error "Z2_USE_ENDSTOP has been assigned to a nonexistent endstop!"
   #elif ENABLED(DELTA)
     #error "Z_DUAL_ENDSTOPS is not compatible with DELTA."
   #endif
diff --git a/Marlin/endstops.cpp b/Marlin/endstops.cpp
index 8cb04979c..9a4a9c84b 100644
--- a/Marlin/endstops.cpp
+++ b/Marlin/endstops.cpp
@@ -157,11 +157,15 @@ void Endstops::report_state() {
       if (TEST(endstop_hit_bits, A ##_MIN) || TEST(endstop_hit_bits, A ##_MAX)) \
         _ENDSTOP_HIT_ECHO(A,C)
 
+    #define ENDSTOP_HIT_TEST_X() _ENDSTOP_HIT_TEST(X,'X')
+    #define ENDSTOP_HIT_TEST_Y() _ENDSTOP_HIT_TEST(Y,'Y')
+    #define ENDSTOP_HIT_TEST_Z() _ENDSTOP_HIT_TEST(Z,'Z')
+
     SERIAL_ECHO_START;
     SERIAL_ECHOPGM(MSG_ENDSTOPS_HIT);
-    _ENDSTOP_HIT_TEST(X, 'X');
-    _ENDSTOP_HIT_TEST(Y, 'Y');
-    _ENDSTOP_HIT_TEST(Z, 'Z');
+    ENDSTOP_HIT_TEST_X();
+    ENDSTOP_HIT_TEST_Y();
+    ENDSTOP_HIT_TEST_Z();
 
     #if ENABLED(Z_MIN_PROBE_ENDSTOP)
       #define P_AXIS Z_AXIS
diff --git a/Marlin/pins.h b/Marlin/pins.h
index 33243bd5e..f223e0c52 100644
--- a/Marlin/pins.h
+++ b/Marlin/pins.h
@@ -461,6 +461,9 @@
     #define X2_STEP_PIN   _EPIN(E_STEPPERS, STEP)
     #define X2_DIR_PIN    _EPIN(E_STEPPERS, DIR)
     #define X2_ENABLE_PIN _EPIN(E_STEPPERS, ENABLE)
+    #if X2_ENABLE_PIN == 0
+      #error "No E stepper plug left for X2!"
+    #endif
   #endif
   #undef _X2_PINS
   #define _X2_PINS X2_STEP_PIN, X2_DIR_PIN, X2_ENABLE_PIN,
@@ -475,6 +478,9 @@
     #define Y2_STEP_PIN   _EPIN(Y2_E_INDEX, STEP)
     #define Y2_DIR_PIN    _EPIN(Y2_E_INDEX, DIR)
     #define Y2_ENABLE_PIN _EPIN(Y2_E_INDEX, ENABLE)
+    #if Y2_ENABLE_PIN == 0
+      #error "No E stepper plug left for Y2!"
+    #endif
   #endif
   #undef _Y2_PINS
   #define _Y2_PINS Y2_STEP_PIN, Y2_DIR_PIN, Y2_ENABLE_PIN,
@@ -489,6 +495,9 @@
     #define Z2_STEP_PIN   _EPIN(Z2_E_INDEX, STEP)
     #define Z2_DIR_PIN    _EPIN(Z2_E_INDEX, DIR)
     #define Z2_ENABLE_PIN _EPIN(Z2_E_INDEX, ENABLE)
+    #if Z2_ENABLE_PIN == 0
+      #error "No E stepper plug left for Z2!"
+    #endif
   #endif
   #undef _Z2_PINS
   #define _Z2_PINS Z2_STEP_PIN, Z2_DIR_PIN, Z2_ENABLE_PIN,