Ford Fiesta: Interior Lighting / Interior Lighting - System Operation and Component Description. Description and Operation

System Operation

System Diagram

Network Message Chart

  BCM Network Input Messages

Battery Saver

NOTE: Time-out is 30 seconds if the vehicle is in Factory or Transport mode.

The BCM provides automatic shut-off of the courtesy and demand lamps after a time-out period when the ignition is OFF. A timer in the BCM starts when:

• the ignition transitions to OFF.
• any door or liftgate/luggage compartment lid becomes ajar.
• an UNLOCK button of the RKE transmitter is pressed.
• a door is unlocked using a key.
• the door lock switch is pressed.

When 10 minutes have elapsed, the BCM automatically shuts off voltage to the lamps. The timer restarts (voltage is restored if the BCM is in battery saver mode) if:

• the ignition transitions out of OFF.
• any door or liftgate/luggage compartment lid becomes ajar.
• the UNLOCK button of the RKE transmitter is pressed.
• a door is unlocked using a key.
• the door lock switch is pressed.

Courtesy Lamps

The BCM controls the courtesy lighting functions and timing by monitoring inputs from the following:

• Door ajar switches
• Ignition state
• RKE system

The BCM sends a voltage signal to each door ajar switch. When the doors are closed, the circuit is switched to ground and the voltage is pulled low, indicating closed doors.

The BCM monitors the ignition state and inputs from the RKE system to determine when to ground the interior lights output. Ground is provided to the interior lamps from the BCM interior lights output. The BCM controls the voltage side of the courtesy lamps for the illuminated entry and exit features.

For keyless entry, the BCM monitors input from the RKE transmitter (directly from the integrated keyhead transmitters [IKTs] on vehicles without push button start) or from the RFA module (on vehicles with push button start) to determine when to activate/deactivate the illuminated entry and exit functions.

The interior courtesy lamps can also be activated from the courtesy lamp switch mounted on the front and rear interior lamp.

Illuminated Entry and Exit

The illuminated entry and exit features provide temporary illumination of the parking lamps, the dimmable backlighting, the ambient backlighting and the courtesy lamps. Refer to the table for additional information.

NOTE: For vehicles without push button start, the timer for the backlighting and ambient lighting is reset to 25 seconds when the key is inserted or removed from the ignition lock cylinder.

Theater Lighting

The theater lighting option ramps-up the courtesy lamps over 0.7 seconds when courtesy lamp is requested. The theater lighting feature ramps-down the courtesy lamps over 1.7 seconds when interior lighting deactivation is requested by any feature other than the panic alarm or battery saver.

Demand Lamps

The demand lamps subsystem consists of the map/reading lamps, glove compartment lamp and the cargo area lamp. The BCM energizes the battery saver output to supply voltage to the demand lamps when the battery saver feature is not active.

Ambient Lighting

The ambient lighting subsystem consists of the BCM , ambient lighting switch, ambient lighting module and the Light Emitting Diodes (LEDs) located within the center console cup holders, the instrument panel and the front and rear footwells. The ambient lighting is operational when the ignition is in any state other than OFF (the exception is when it is used in conjunction with the illuminated entry/exit features), the headlamps are on and the outside ambient light level is low. The ambient lighting switch cycles the Light Emitting Diodes (LEDs) through 7 different color combinations or to turn the ambient lighting off.

Component Description

Door Ajar Switch

The door ajar switches (ground switches) each receive a voltage signal from the BCM on independent circuits. When the door is closed, the door ajar switch is closed, routing the signal to ground. When the door is opened, the door ajar switch opens.