diff --git a/conf/firmwares/test_progs.makefile b/conf/firmwares/test_progs.makefile
index 823df172a5..b58fe98364 100644
--- a/conf/firmwares/test_progs.makefile
+++ b/conf/firmwares/test_progs.makefile
@@ -91,12 +91,12 @@ LED_DEFINES ?= -DLED_RED=2 -DLED_GREEN=3
 test_sys_time_timer.ARCHDIR = $(ARCH)
 test_sys_time_timer.CFLAGS += $(COMMON_TEST_CFLAGS) $(LED_DEFINES)
 test_sys_time_timer.srcs   += $(COMMON_TEST_SRCS)
-test_sys_time_timer.srcs   += $(SRC_AIRBORNE)/test/mcu_periph/test_sys_time_timer.c
+test_sys_time_timer.srcs   += test/mcu_periph/test_sys_time_timer.c
 
 test_sys_time_usleep.ARCHDIR = $(ARCH)
 test_sys_time_usleep.CFLAGS += $(COMMON_TEST_CFLAGS) $(LED_DEFINES)
 test_sys_time_usleep.srcs   += $(COMMON_TEST_SRCS)
-test_sys_time_usleep.srcs   += $(SRC_AIRBORNE)/test/mcu_periph/test_sys_time_usleep.c
+test_sys_time_usleep.srcs   += test/mcu_periph/test_sys_time_usleep.c
 
 
 #
diff --git a/sw/airborne/test/mcu_periph/test_sys_time_timer.c b/sw/airborne/test/mcu_periph/test_sys_time_timer.c
index 2d7607544a..46d721baf2 100644
--- a/sw/airborne/test/mcu_periph/test_sys_time_timer.c
+++ b/sw/airborne/test/mcu_periph/test_sys_time_timer.c
@@ -23,6 +23,7 @@
 #include "mcu.h"
 #include "led.h"
 #include "mcu_periph/sys_time.h"
+#include "interrupt_hw.h"
 
 static inline void main_periodic_02( void );
 static inline void main_periodic_03( void );
@@ -36,6 +37,8 @@ int main(void) {
   unsigned int tmr_03 = sys_time_register_timer(0.3, NULL);
   sys_time_register_timer(0.5, main_periodic_05);
 
+  mcu_int_enable();
+
   while(1) {
     if (sys_time_check_and_ack_timer(tmr_02))
       main_periodic_02();
diff --git a/sw/airborne/test/mcu_periph/test_sys_time_usleep.c b/sw/airborne/test/mcu_periph/test_sys_time_usleep.c
index 6aafc0ae02..cda5dbd4eb 100644
--- a/sw/airborne/test/mcu_periph/test_sys_time_usleep.c
+++ b/sw/airborne/test/mcu_periph/test_sys_time_usleep.c
@@ -23,6 +23,7 @@
 #include "mcu.h"
 #include "led.h"
 #include "mcu_periph/sys_time.h"
+#include "interrupt_hw.h"
 
 static inline void main_periodic_1(void);
 static inline void main_periodic_15(void);
@@ -33,6 +34,8 @@ int main(void) {
   mcu_init();
   sys_time_register_timer(0.5, main_periodic_05);
 
+  mcu_int_enable();
+
   while(1) {
     /* sleep for 1s */
     sys_time_usleep(1000000);