System Overview

System overview

Subwoofer module (SUB)
The primary task of the subwoofer module (SUB) is to manage sound reproduction from the audio module (AUD) to the bass loudspeaker.
The bass loudspeakers and amplifier are integrated into the control module. This means that the whole unit must be replaced when replacing the control module.
The subwoofer module (SUB) only functions if the audio module (AUD) is connected to the MOST network.
The subwoofer module (SUB) checks activations and input and output signals via an integrated diagnostic system. A diagnostic trouble code (DTC) is stored if the control module detects a fault. Any diagnostic trouble codes (DTCs) are stored in the control module memory.
The subwoofer module (SUB) uses the MOST network to communicate with other control modules.
In order to work correctly on the MOST network, the infotainment control module (ICM) checks that the serial number in the subwoofer module (SUB) is correct. The subwoofer module (SUB) will not function if the number is incorrect. Try switching the ignition off and on if there are problems when replacing the control module.
A simple way to check whether the subwoofer module (SUB) is functioning is to switch on the radio and to then change the volume. The volume from the subwoofer module (SUB) should rise and fall with the changes.

Note! Ensure that the bass loudspeaker is selected in the infotainment control module (ICM). Turn the SEL button on the infotainment control module (ICM).

The subwoofer module (SUB) is on the left-hand side of the cargo compartment.

Signals
The table below summarizes the input signals to and output signals from the subwoofer module (SUB) on the MOST network. The illustration below displays the same information with the Volvo component designations.