Interior Roof Lighting
There are a number of lamps inside the passenger compartment. The lamps include four reading lamps and a general courtesy lamp.
In XC90 models with three rows of seats there are 6 reading lamps.
The front left and front right reading lamps and the courtesy light are located in the same unit in the roof, just above the rear view mirror. The other reading lamps are in the roof above the rear seat(s).
These lamps transmit control signals to the control module. These signals allow the control module to determine the status of the lamps and switches. This allows any faults to be detected. For example:
- a blown bulb
- an open-circuit in a cable
- that the switch has jammed in the pressed in position.
The control signals are divided up as input signals at a number of inputs in the upper electronic module (UEM). The control signal for the courtesy lighting shares the same inputs as control signals for the front reading lamps. The rear control signals for the reading lamps each have their own input. If there is a third row of seats, there is a separate input for the control signals for this row.
Two different lighting times can be programmed using VIDA depending on the requirements of the customer. For further information, see: DOWNLOADING SOFTWARE AND REPLACING THE CONTROL MODULE
There are diagnostics for all lamps in the inner roof lighting.