diff --git a/samples/boards/stm32/power_mgmt/serial_wakeup/prj.conf b/samples/boards/stm32/power_mgmt/serial_wakeup/prj.conf
index 3e1a61bf9db..ca1e6cf73a9 100644
--- a/samples/boards/stm32/power_mgmt/serial_wakeup/prj.conf
+++ b/samples/boards/stm32/power_mgmt/serial_wakeup/prj.conf
@@ -1,7 +1,8 @@
 CONFIG_PM=y
 CONFIG_PM_DEVICE=y
-CONFIG_PM_DEVICE_RUNTIME=n
-CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE=n
+CONFIG_PM_DEVICE_RUNTIME=y
+CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE=y
+
 CONFIG_SHELL=y
 
 CONFIG_DEBUG=n
diff --git a/samples/boards/stm32/power_mgmt/serial_wakeup/sample.yaml b/samples/boards/stm32/power_mgmt/serial_wakeup/sample.yaml
index 42528be505d..e0f61361500 100644
--- a/samples/boards/stm32/power_mgmt/serial_wakeup/sample.yaml
+++ b/samples/boards/stm32/power_mgmt/serial_wakeup/sample.yaml
@@ -4,8 +4,6 @@ tests:
   sample.boards.stm32.power_mgmt.serial_wakeup:
     tags:
       - UART
-      - Wake
-      - up
       - power
     harness: console
     harness_config:
diff --git a/samples/boards/stm32/power_mgmt/serial_wakeup/src/main.c b/samples/boards/stm32/power_mgmt/serial_wakeup/src/main.c
index 74284abf41b..35846c04411 100644
--- a/samples/boards/stm32/power_mgmt/serial_wakeup/src/main.c
+++ b/samples/boards/stm32/power_mgmt/serial_wakeup/src/main.c
@@ -24,7 +24,8 @@ int main(void)
 #if CONFIG_PM_DEVICE
 	/* In PM_DEVICE modes, enable device as a wakeup source will prevent
 	 * system to switch it off (clock off, set pins to sleep configuration, ...)
-	 * It is not requested in PM mode only since this mode will not
+	 * It is not requested in CONFIG_PM mode only as in this case, device is not
+	 * suspended before stop mode entry.
 	 */
 
 	bool ret;