A vehicle electrical power supply arrangement includes a towing vehicle, a primary power supply source position within the towed vehicle, a towed vehicle operably coupled to the towing vehicle for towing behind the towing vehicle, wherein the towed vehicle is configured to be electrically coupled and uncoupled from the towing vehicle, an auxiliary power supply source positioned within the towed vehicle and configured to store an electronic charge, a sensor arrangement attached to the towed vehicle and configured to monitor a vehicle operating parameter, and an electronic control unit operably coupled to the sensor arrangement, wherein the electronic control unit is configured to receive an electrical charge from at least one of the primary power source and the auxiliary power source when the towed vehicle is electrically coupled to the towing vehicle, and from the auxiliary power source when the towed vehicle is electrically uncoupled from the towing vehicle.