Instruments and controlsMechanically operated main switchesonly have a switch outside the cabin.3D002104-23.4 TELEPHONE3.4.1 Telephone interfaceThe telephone interface provides hands-free telephone operation either by connectingBluetooth enabled telephones or by activating the truck phone.See section 'Installing and removing Bluetooth enabled telephones' or section'Activating the truck phone'.The telephone interface is fully functional when the ignition is switched on or at leastplaced in the accessory position.When the ignition is switched off active calls are supported provided they were activebefore the ignition was switched off.With the ignition off and the active call ended the telephone interface no longersupports Bluetooth connected phones.However the truck phone will still receive incoming phone calls and SMS messages fora period of 24 hours after the ignition is switched off.