Power is supplied from the CD/PH fuse in the rear fuse block to the cellular telephone module and to the cellular telephone handset. The module is grounded at ground G202.

Power is supplied to the cellular telephone handset from the RDO/PH fuse in the rear fuse block when ignition is in RUN or ACC and during retained accessory power. The handset is grounded at ground G202. The handset contains a keypad, display, microphone and ear speaker. The handset communicates signals to the cellular telephone module by coax cable.

When the handset is placed in its docking cup, the phone operates in the hands-free mode. This mode allows the driver's voice to be received by the roof-mounted microphone. During hands-free mode, the vehicle radio mutes and the incoming cellular telephone audio is routed through the radio's speakers. When the handset is removed from its cup, the hands-free feature is disabled and the audio system is no longer muted. The handset must be held to the driver's head for voice conversation.

The cellular telephone microphone is wired to the cellular telephone handset. During hands-free operation, the module provides stereo audio output to the vehicle audio system.

The module communicates on the Class 2 serial data line, which the module uses for transmission of messages, status and diagnostic information.