Rear 12V socket

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Fig 1: Identifying Rear 12V Socket Communication Links & Components

Courtesy of VOLVO CARS OF NORTH AMERICA.

When a power consuming component is connected to the rear 12V socket (17/19), the power consumption is measured via a shunt inside the rear electronic module (REM) (4/58). The rear electronic module (REM) transmits status data via the controller area network (CAN) to the driver information module (DIM) (5/1) which displays a text message.

The text message is also displayed if a power consuming component is connected when changing from ignition position:

II to I
I to 0 and
0 to the key is removed.

There is also an audible warning note when the key is removed.