diff --git a/libraries/AP_HAL_ChibiOS/hwdef/MatekL431-Rangefinder/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/MatekL431-Rangefinder/hwdef.dat
index 0a2ddad959136..99e189f4b3b39 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/MatekL431-Rangefinder/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/MatekL431-Rangefinder/hwdef.dat
@@ -6,6 +6,7 @@ define HAL_DISABLE_ADC_DRIVER TRUE
 
 # support all rangefinder types
 define HAL_PERIPH_ENABLE_RANGEFINDER
+define RANGEFINDER_MAX_INSTANCES 2
 
 define AP_PERIPH_RANGEFINDER_PORT_DEFAULT 2