diff --git a/flash/FP4/flash_FP4_factory.sh b/flash/FP4/flash_FP4_factory.sh
index 06764a1c1ed8939ae5fedf20973202bfbb23e844..608b770aac08ccae726035b0e5e0396514497b56 100755
--- a/flash/FP4/flash_FP4_factory.sh
+++ b/flash/FP4/flash_FP4_factory.sh
@@ -7,7 +7,7 @@
 ##########
 
 ##########
-# This script flashes a software release and complete wipes the device.
+# This script flashes a software release and completely wipes the device.
 #
 ##########
 
@@ -55,8 +55,7 @@ find_device() {
         echo "WARNING: Make sure that a ${PRODUCT} is connected."
         ;;
       1)
-          echo "INFO: One ${PRODUCT} in fastboot mode found (serial number: ${sn})."
-
+        echo "INFO: One ${PRODUCT} in fastboot mode found (serial number: ${sn})."
         DEVICE_FOUND="true"
         break
         ;;
@@ -82,9 +81,38 @@ find_device() {
   done
 }
 
+# Check if the device is properly unlocked
+check_unlock_status() {
+  PHONE_IS_READY=true
+  if (fastboot getvar is-userspace 2>&1 | grep -q yes); then
+    echo "Info: Your phone is in fastbootD mode."
+    if (fastboot getvar unlocked 2>&1 | grep -q no); then
+      echo "Error: Your phone is still locked."
+      echo "Did you execute 'fastboot flashing unlock'?"
+      PHONE_IS_READY=false
+    fi
+  else
+    echo "Info: Your phone is in regular bootloader mode."
+    if (fastboot getvar unlocked 2>&1 | grep -q no); then
+      echo "Error: Your phone is still locked."
+      echo "Did you execute 'fastboot flashing unlock'?"
+      PHONE_IS_READY=false
+    fi
+    if (fastboot oem device-info 2>&1 | grep -q "critical unlocked: false"); then
+      echo "Error: Critical partitions are still locked."
+      echo "Did you execute 'fastboot flashing unlock_critical'?"
+      PHONE_IS_READY=false
+    fi
+  fi
+
+  if [ "$PHONE_IS_READY" = "false" ]; then
+    echo "Error: Your phone is not ready for flashing yet (see above), aborting..."
+    exit 1
+  fi
+}
+
 # Flash (or manipulate) relevant partitions
 flash_device() {
-
   flash_image_ab_or_abort "${sn}" bluetooth "${IMAGES_DIR}/bluetooth.img"
   flash_image_ab_or_abort "${sn}" devcfg "${IMAGES_DIR}/devcfg.img"
   flash_image_ab_or_abort "${sn}" dsp "${IMAGES_DIR}/dsp.img"
@@ -115,7 +143,6 @@ flash_device() {
   "$FASTBOOT_BIN" -s "${sn}" erase metadata
 
   "$FASTBOOT_BIN" -s "${sn}" --set-active=a
-
 }
 
 # Flash an image to a partition. Abort on failure.
@@ -137,7 +164,7 @@ flash_image_or_abort() {
   fi
 }
 
-# Flash an image to both A and B slot of partition. Abort on failure.
+# Flash an image to both A and B slots of a partition. Abort on failure.
 # Arguments: <device serial number> <partition name without slot> <image file>
 flash_image_ab_or_abort() {
   flash_image_or_abort "${1}" "${2}_a" "${3}"
@@ -192,6 +219,9 @@ os_checks
 # If only one device is found $sn will store its serial number
 find_device
 
+# Check if the device is properly unlocked
+check_unlock_status
+
 # Flash the device
 flash_device