diff --git a/libraries/AP_HAL_ChibiOS/hwdef/CubeRedPrimary/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/CubeRedPrimary/hwdef.dat
index 5bd8d3c71c..a7a89aaae7 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/CubeRedPrimary/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/CubeRedPrimary/hwdef.dat
@@ -125,6 +125,7 @@ BARO MS56XX SPI:ms5611_0
 BARO MS56XX SPI:ms5611_1
 
 COMPASS RM3100 SPI:rm3100 false ROTATION_YAW_270 
+define HAL_PROBE_EXTERNAL_I2C_COMPASSES
 
 CHECK_ICM20649        spi_check_register_inv2("icm20649", INV2REG_WHOAMI, INV2_WHOAMI_ICM20649)
 CHECK_ICM45686_2      spi_check_register("icm45686", INV3REG_456_WHOAMI, INV3_WHOAMI_ICM45686)