diff --git a/board/eltec/mhpc/flash.c b/board/eltec/mhpc/flash.c
index 58cfd70..e9c8f98 100644
--- a/board/eltec/mhpc/flash.c
+++ b/board/eltec/mhpc/flash.c
@@ -92,7 +92,7 @@
 	/* monitor protection ON by default */
 	(void)flash_protect(FLAG_PROTECT_SET,
 			    CFG_FLASH_BASE,
-			    CFG_FLASH_BASE+CFG_MONITOR_LEN-1,
+			    CFG_FLASH_BASE+monitor_flash_len-1,
 			    &flash_info[0]);
 
 	flash_info[0].size = size_b0;