Interior courtesy lamps (Body control unit)

The BCU checks the status of the following inputs to determine the logic action for providing an output to the rear fog lamp relay: l Ignition state. l Main beam state. l Dipped beam. l Front fogs relay. l Rear fogs selected (press button, not latched).

If the ignition state is crank the state of the rear fog relay is memorised and the relay is switched off. Pressing the front fog switch during cranking will not be recognised. When the ignition state returns to Ignition after cranking, the memorised rear fog relay state is restored. If the ignition is turned off, the rear fog relay is turned off.

In the event of a communications link failure occurring while the rear fog relay is on, the rear fog relay will remain on until the ignition is turned off or the dipped/ main beam is turned off.

Interior courtesy lamps

To determine when to provide an interior courtesy lamps enable output, the BCU checks the following input conditions: l Ignition state. l Transit mode. l Driver's door open. l Passenger or rear door open.

The courtesy lamps operate at full brightness when they are first switched on. The BCU then gradually dims the lamps (fade-out) before completely switching them off. Fade-out occurs over a period of two seconds following the logical control signal to turn off the lights. When a door is opened, the BCU provides earth paths from the interior lamps, the load space lamp and the ignition switch illumination. The following table lists the courtesy lamps operation and duration for holding the lamps on that occurs after the BCU has detected a condition that signals the courtesy lamps should be switched on:

Instrument pack

The BCU communicates with the instrument pack to provide a range of functions.