diff --git a/libraries/AP_HAL_ChibiOS/hwdef/JHEMCU-GSF405A/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/JHEMCU-GSF405A/hwdef.dat
index b47ea2582a..7b98f93828 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/JHEMCU-GSF405A/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/JHEMCU-GSF405A/hwdef.dat
@@ -157,6 +157,7 @@ define HAL_WITH_DSP FALSE
 # --------------------- save flash ----------------------
 define AP_BATTMON_SMBUS_ENABLE 0
 define AP_BATTMON_FUEL_ENABLE 0
+define AP_BATT_MONITOR_MAX_INSTANCES 1
 define HAL_PARACHUTE_ENABLED 0
 define HAL_SPRAYER_ENABLED 0
 define HAL_GENERATOR_ENABLED 0