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Interior Roof Lighting

Fig 1: Identifying Interior Roof Lighting Communication Links & Components
GLL146363Courtesy of VOLVO CARS CORPORATION

The interior roof lighting and reading lamps, front (3/117) and rear (10/150) are controlled via the upper electronic module (UEM) (4/70) in that they are supplied with voltage directly from the control module when each switch is activated. The courtesy lighting is also activated when the doors are opened or when approach lighting is activated.

Data is sent to the upper electronic module (UEM) from the rear electronic module (REM) (4/58) via the controller area network (CAN). This data indicates which doors or tailgate/trunk lid are opened or closed.

The request for keyhole lighting, courtesy lighting and cargo compartment lighting is sent from the upper electronic module (UEM) to the central electronic module (CEM) (4/56) and rear electrical module (REM) via the controller area network (CAN).

The cargo compartment lighting in the V70 and XC70 (10/25) is powered by the upper electronic module (UEM). The lamp is activated if the upper electronic module (UEM) receives information from the rear electronic module (REM) indicating that the tailgate is open.

The sun visor lighting (10/114-115) is powered by the upper electronic module (UEM) using the voltage supply signal EXT. X. The lamp is activated when the flap covering the mirror in the sun visor is opened.