Aspects of the present invention relate to a method, a control system, a vehicle, a system, and a non-transitory computer readable medium. Application program code is downloaded to the control system via an interface and installed on the control system. Then, it is determined whether the control system is able to communicate with an external device via the interface while running the installed application program code, and the installed application program code is subsequently loaded on startup of the control system in dependence on a determination that the control system was able to communicate with the external device.