diff --git a/firmware/bootloader/openblt_chibios/openblt_usb.cpp b/firmware/bootloader/openblt_chibios/openblt_usb.cpp
index 469f74d41b..b326c2c385 100644
--- a/firmware/bootloader/openblt_chibios/openblt_usb.cpp
+++ b/firmware/bootloader/openblt_chibios/openblt_usb.cpp
@@ -7,9 +7,16 @@ extern "C" {
 	#include "rs232.h"
 }
 
+extern blt_bool stayInBootloader;
+
 void Rs232Init() {
-	// Set up USB serial
-	usb_serial_start();
+#if (BOOT_BACKDOOR_ENTRY_TIMEOUT_MS == 0)
+	if (stayInBootloader || (NvmVerifyChecksum() == BLT_FALSE))
+#endif
+	{
+	  // Set up USB serial
+  	usb_serial_start();
+	}
 }
 
 #define RS232_CTO_RX_PACKET_TIMEOUT_MS (100u)