🐛 Fix DETECT_BROKEN_ENDSTOP on IDEX (#26790)

Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>

Marlin/src/module/motion.cpp

@@ -2183,18 +2183,28 @@ void prepare_line_to_destination() {
       do_homing_move(axis, -bump, TERN(HOMING_Z_WITH_PROBE, (axis == Z_AXIS ? z_probe_fast_mm_s : 0), 0), false);
 
       #if ENABLED(DETECT_BROKEN_ENDSTOP)
+
         // Check for a broken endstop
         EndstopEnum es;
         switch (axis) {
           #define _ESCASE(A) case A##_AXIS: es = A##_ENDSTOP; break;
           MAIN_AXIS_MAP(_ESCASE)
           default: break;
         }
+
+        #if ENABLED(DUAL_X_CARRIAGE)
+          if (axis == X_AXIS && axis_home_dir > 0) {
+            es = X_MAX;
+            if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("DUAL_X_CARRIAGE: Homing to X_MAX");
+          }
+        #endif
+
         if (TEST(endstops.state(), es)) {
           SERIAL_ECHO_MSG("Bad ", C(AXIS_CHAR(axis)), " Endstop?");
           kill(GET_TEXT_F(MSG_KILL_HOMING_FAILED));
         }
-      #endif
+
+      #endif // DETECT_BROKEN_ENDSTOP
 
       #if ALL(HOMING_Z_WITH_PROBE, BLTOUCH)
         if (axis == Z_AXIS && !bltouch.high_speed_mode && bltouch.deploy())