From 604c09e6787afec4aad84674896d248a5541336a Mon Sep 17 00:00:00 2001
From: ellensp <530024+ellensp@users.noreply.github.com>
Date: Tue, 10 Feb 2026 18:41:48 +1300
Subject: [PATCH 1/2] add sd detect and SD_MAX_READ_ERRORS

---
 Marlin/Configuration_adv.h |  5 +++++
 Marlin/src/core/language.h |  2 ++
 Marlin/src/gcode/queue.cpp | 21 ++++++++++++++++++++-
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/Marlin/Configuration_adv.h b/Marlin/Configuration_adv.h
index 84fbd6f8ed..15b5684a86 100644
--- a/Marlin/Configuration_adv.h
+++ b/Marlin/Configuration_adv.h
@@ -1886,6 +1886,11 @@
     #if ENABLED(POWER_LOSS_RECOVER_ZHOME)
       //#define POWER_LOSS_ZHOME_POS { 0, 0 } // Safe XY position to home Z while avoiding objects on the bed
     #endif
+
+    // Maximum number of consecutive SD card read errors before aborting the print
+    // Prevents infinite loops when reading from SD card with hardware/communication faults
+    #define SD_MAX_READ_ERRORS 5
+
   #endif
 
   /**
diff --git a/Marlin/src/core/language.h b/Marlin/src/core/language.h
index 837f3885b9..b9ab7c850e 100644
--- a/Marlin/src/core/language.h
+++ b/Marlin/src/core/language.h
@@ -184,6 +184,8 @@
 #define STR_SD_NOT_PRINTING                 "Not SD printing"
 #define STR_SD_ERR_WRITE_TO_FILE            "error writing to file"
 #define STR_SD_ERR_READ                     "SD read error"
+#define STR_SD_ERR_TOO_MANY_READ_ERRORS     "Too many SD read errors, print aborted"
+#define STR_SD_ERR_CARD_REMOVED             "SD card removed, print aborted"
 #define STR_SD_CANT_ENTER_SUBDIR            "Cannot enter subdir: "
 
 #define STR_ENDSTOPS_HIT                    "endstops hit: "
diff --git a/Marlin/src/gcode/queue.cpp b/Marlin/src/gcode/queue.cpp
index 0014ca44a5..011c23afff 100644
--- a/Marlin/src/gcode/queue.cpp
+++ b/Marlin/src/gcode/queue.cpp
@@ -570,11 +570,30 @@ void GCodeQueue::get_serial_commands() {
     // Get commands if there are more in the file
     if (!card.isStillFetching()) return;
 
+    #if HAS_SD_DETECT
+      // Abort print if SD card was removed mid-print
+      if (!card.isInserted()) {
+        SERIAL_ERROR_MSG(STR_SD_ERR_CARD_REMOVED);
+        card.abortFilePrintNow();
+        return;
+      }
+    #endif
+
     int sd_count = 0;
+    uint16_t sd_read_errors = 0;
     while (!ring_buffer.full() && !card.eof()) {
       const int16_t n = card.get();
       const bool card_eof = card.eof();
-      if (n < 0 && !card_eof) { SERIAL_ERROR_MSG(STR_SD_ERR_READ); continue; }
+      if (n < 0 && !card_eof) {
+        SERIAL_ERROR_MSG(STR_SD_ERR_READ);
+        if (++sd_read_errors >= SD_MAX_READ_ERRORS) {
+          SERIAL_ERROR_MSG(STR_SD_ERR_TOO_MANY_READ_ERRORS);
+          card.abortFilePrintNow();
+          break;
+        }
+        continue;
+      }
+      sd_read_errors = 0; // Reset on successful read
 
       CommandLine &command = ring_buffer.commands[ring_buffer.index_w];
       const char sd_char = (char)n;

From 204ba64266e5de26e4a1e3fc1a0fb76f396f002e Mon Sep 17 00:00:00 2001
From: ellensp <530024+ellensp@users.noreply.github.com>
Date: Tue, 10 Feb 2026 19:17:58 +1300
Subject: [PATCH 2/2] move SD_MAX_READ_ERRORS

---
 Marlin/Configuration_adv.h | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/Marlin/Configuration_adv.h b/Marlin/Configuration_adv.h
index 15b5684a86..2dae863006 100644
--- a/Marlin/Configuration_adv.h
+++ b/Marlin/Configuration_adv.h
@@ -1886,11 +1886,6 @@
     #if ENABLED(POWER_LOSS_RECOVER_ZHOME)
       //#define POWER_LOSS_ZHOME_POS { 0, 0 } // Safe XY position to home Z while avoiding objects on the bed
     #endif
-
-    // Maximum number of consecutive SD card read errors before aborting the print
-    // Prevents infinite loops when reading from SD card with hardware/communication faults
-    #define SD_MAX_READ_ERRORS 5
-
   #endif
 
   /**
@@ -2066,6 +2061,10 @@
     #define DEFAULT_SHARED_VOLUME USB_FLASH_DRIVE  // :[ 'SD_ONBOARD', 'USB_FLASH_DRIVE' ]
   #endif
 
+  // Maximum number of consecutive SD card read errors before aborting the print
+  // Prevents infinite loops when reading from SD card with hardware/communication faults
+  #define SD_MAX_READ_ERRORS 5
+
 #endif // HAS_MEDIA
 
 /**