System Overview: Signals

WARNING: This page is about a different variant/trim than selected.

The table below summarizes the input signals to and output signals from the accessory electronic module (AEM) (4/78).

The signal types are divided into directly connected signals and Controller area network (CAN) communication. The illustration below displays the same information with the Volvo component designations.

NOTE:

The signals are only available for installed accessories.

Input signals	Output signals
Directly connected: The telemute signal from after market hands free unit to the carphone to mute the volume on the sound system.	Directly connected: Start for the parking heater consisting of +12 V to the relay for the electrical parking heater External alarm unit (status signals).
Via Controller Area Network (CAN) communication:	Via Controller Area Network (CAN) communication:
Central electronic module (CEM) (4/56): Start and stop signal, to control the relay for the electrical parking heater Alarm status, door status, key status. Used by the accessory electronic module (AEM) to control the external alarm. Steering wheel module (SWM) (3/254): Manual start and stop signal, to control the relay for the electrical parking heater. Via central electronic module (CEM).	Infotainment control module (ICM) (16/1): Telemute signal via infotainment control module (ICM) via the MOST network to the audio module (AUD). Central electronic module (CEM) (4/56): Start and stop signal, to control the relay for the electrical parking heater Start and stop signal, to control the combustion preheater module (CPM) (for fuel driven parking heaters).

Fig 1: Identifying AEM & Components

Courtesy of VOLVO CARS OF NORTH AMERICA.