Loader BSL pin's main purpose is for factory use, but it can also be used for resetting the control unit to factory settings (application and all parameters are removed, node-IDs are reset).
In case the control unit (FW version 1.170 or newer) is not responding to CAN messages, use the BSL pin to reset the control unit:
1. Disconnect the power from the control unit
2. Connect the BSL pin to ground
3. Power up the unit
4. Wait for 10 seconds
5. Power off the unit, disconnect the BSL pin from ground and then power up the unit
6. The unit is now restored to factory settings