Adaptive Front Lighting System (AFS)

WARNING: This page is about a different car, the 2018 Jaguar XE and 2017 Jaguar XE. However, it is still accessible from the selected car via links, so may be relevant.

The Adaptive Front lighting System (AFS) headlamp assembly contains an additional carrier frame which provides a location for the horizontal actuator. The projector module has a central pivot point which allows the module to move horizontally in response to operation of the horizontal actuator.

The AFS actuators are bi-polar (two phase) Direct Current (DC) stepper motors which are driven by a power output from the AFS power module located in the headlamp assembly. Each stepper motor receives its position information from the Headlamp Leveling Control Module (HLCM) via the applicable AFS power module. When the actuators are powered to their requested positions, a holding current is applied to maintain the actuator position.

The actuators do not supply a positional feedback signal to the HLCM. Each stepper motor requires referencing each time the AFS system becomes active. When the AFS system is active, each vertical actuator is driven to the low beam position and each horizontal actuator is driven to an inboard position until a mechanical stop in the actuator is reached. Once the stop is reached a step counter in the HLCM is set to zero and the actuator is then powered to the operating position as determined by the AFS software.

The AFS is controlled by the BCM/GWM assembly. The BCM/GWM assembly can process and control the headlamp leveling and the AFS headlamp systems. The BCM/GWM assembly is used on vehicles without AFS but fitted with xenon headlamps.

The system operates by the BCM/GWM assembly receiving inputs from the Powertrain Control Module (PCM) for engine running signal, the Anti-lock Brake System (ABS) control module for steering angle and vehicle speed and a reverse gear input from the transmission.

The BCM/GWM assembly processes these signals and provides an output to the headlamp leveling motors to adjust the headlamp horizontal aim according to vehicle speed and steering angle.

NOTE: In markets with DRL, the AFS system will not operate when the DRL are active.

The BCM/GWM assembly is connected to the AFS headlamps on LIN bus. The BCM/GWM assembly calculates, using input data from other systems, the required position of the horizontal adjustment of the projector modules. The position information is then output on the LIN bus to the AFS headlamps. The BCM/GWM assembly outputs the appropriate signals to drive the AFS stepper motors in the headlamp to the appropriate position.

The horizontal position of the projector modules is dependent on a number of input variables. The position is determined by vehicle speed and steering angle. When reverse gear is selected, the projector modules are moved to the straight ahead position to avoid glare to other road users.

The angles of each projector module differ to give the correct spread of light, for example, when turning left, the left hand projector module will have a greater swivelling angle than the right hand projector module.