System overview: Signals

The following table summarizes the input signals to and output signals from the phone module (PHM). The signal types are divided into directly connected signals, serial communication and Controller area network (CAN) communication. The following graphic displays the same information with the Volvo component designations.

Input signals	Output signals
Directly connected:	Directly connected: (power supply unless otherwise stated)
Car phone antenna (16/64) (via phone box) Handsfree microphone (16/77) (via phone box) Microphone, handset (16/62).	Car phone antenna (16/64) (via phone box) Handsfree speaker (16/78) Loudspeaker, handset (16/62).
Via serial communication:	Via serial communication:
Phone box (16/66).	Phone box (16/66).
Via Controller Area Network (CAN) communication:	Via Controller Area Network (CAN) communication:
Central electronic module (CEM) (4/56) Steering wheel module (SWM) (3/130) Driver information module (DIM) (5/1) Anti-lock brake system module (ABS) (4/16).	Central electronic module (CEM) (4/56) Driver information module (DIM) (5/1) Audio module (AUM) (16/1).

Fig 1: Input Signals To And Output Signals From Phone Module (PHM)

Courtesy of VOLVO CARS OF NORTH AMERICA.