A vehicle includes a modem and a processor. The processor is programmed to provision the modem, over a local network connection, to perform vehicle-to-vehicle communications, the provisioning being performed independent of access to a cellular communications network, and once provisioned, communicate with a second vehicle over a direct vehicle-to-vehicle connection. The modem may be tested utilizing a Protocol Implementation Conformance Statement (PICS) separating test cases for use of a PC5 interface only, for use of a Uu interface only, and for a hybrid for use of Uu and PC5.