A dual battery electrical system for a vehicle having an engine comprises a primary load and a secondary load and is switchable between an ON state in which the engine is running, an OFF state in which the engine is not running, a START state in which the primary load requires power to start the engine, and a PAUSE state in which the engine is not running. A first battery powers the primary load, a second battery powers the secondary load, a battery switch is closable to connect the first battery to the second battery such that both batteries can provide power to both loads. The transition to and from the OFF state is via a user activated mechanism and transition to and from the PAUSE state is via a user-independent mechanism. A controller controls operation of the battery switch when the system enters and/or leaves the PAUSE state.