diff --git a/libraries/AP_HAL_ChibiOS/hwdef/CUAV_GPS/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/CUAV_GPS/hwdef.dat
index 4556f75d2f..faee842700 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/CUAV_GPS/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/CUAV_GPS/hwdef.dat
@@ -90,6 +90,7 @@ PB10 TIM2_CH3 TIM2 GPIO(77) LOW ALARM
 
 # safety LED, active low
 PB1 SAFE_LED OUTPUT HIGH
+define SAFE_LED_ON 0
 
 define HAL_BARO_ALLOW_INIT_NO_BARO