Adaptive Headlight II (AHL2)
AHL2 was introduced with the E60. It requires Xenon HID or LED headlights. AHL2 varies the light distribution of the low beam.
Engine start
In switch position "A" (light switch in the switch position for automatic driving lights control) and terminal 15 ON, both headlights execute a reference run. That means: Both swivel modules are moved down slightly and then to the desired position (visible when the vehicle is parked in front of a wall: The light cone moves down and then back up). The desired position depends on the load status of the vehicle. When the engine is started, the headlight driver module initially controls the city light distribution.
City light distribution (Town light)
The city light distribution enables a broader illumination of the left roadway at low speeds. The left headlight is moved approximately 12° to the left and approximately 0.7° downwards. The city light distribution is activated from engine start to a driving speed of approximately 50 km/h.
Pertinent Parameter:
C_AFS_C_V_LO defaultwert = 28 (40 km/h, 25 mph)
Country road light distribution (Basic light)
The country road light distribution is the same as the standard low beam headlights. At a driving speed above approximately 50 km/h, the city light distribution is changed to the country road light distribution. Below a driving speed of approximately 50 km/h, the footwell module (FRM) changes the light distribution back to city. The country road light distribution represents the basic setting for the headlights.
Motorway light distribution
The motorway light distribution increases the range of the driving light. The left headlight is moved approximately 3.5° to the left and approximately 0.25° downwards. The right headlight is moved approximately 0.2° upward. If the vehicle speed exceeds 110 km/h for longer than 30 seconds, or if 140 km/h is exceeded, the footwell module switches on the motorway light distribution. If the vehicle speed drops below 110 km/h, the headlights are gradually reset, depending on the driving speed. This takes places in stages (110 km/h 100 km/h 90 km/h 80 km/h). The country road light distribution is activated again at 80 km/h and below.
Pertinent Parameters:
C_AFS_C_V_HI defaultwert = 8C (140 km/h, 87 mph)
C_AFS_E_V_LO defaultwert = 6E (110 km/h, 68 mph) (see timer below)
C_AFS_E1_V_LO defaultwert = 64 (100 km/h, 62 mph)
C_AFS_E2_V_LO defaultwert = 5A (90 km/h, 56 mph)
C_AFS_E3_V_LO defaultwert = 50 (80 km/h, 50 mph)
C_AFS_E_T_MIN defaultwert = 1E (30s)
Comment = Counter Minimum for LightDistribution E
Fog light distribution
The fog light distribution is activated when the fog lights are switched on. The fog light distribution can be combined with the city light distribution and the country road light distribution. The left headlight is moved approximately 8° to the left and approximately 0.7° downwards. If the high beam headlights are switched on while the fog light distribution is active, the headlight moves to the basic setting, i.e. to the country road light distribution.
Pertinent Parameter:
C_AFS_EX_FOG_ENA defaultwert = 01
Comment = Switch to enable or disable motorway light distribution while fog lights are turned on (1 means motorway light distribution enabled).
(Source: http://f80.bimmerpost.com/forums/showpost.php?p=19916060&postcount=31)
In the US, vehicle option 8S4 Variable Light Distribution Decoding actually disables (de-code) VLD. Do not remove 8S4 as it may interfere with software update performed by a BMW Center.
Instead, VLD can be simply enabled via coding with NCS Expert or E-Sys (depending on your vehicle chassis.
For my E60, I use NCS Expert and NCS Dummy to enable VLD:
AHL2_ENABLE = aktiv
AHL2_ENABLE = aktiv
For the F30, I use E-Sys to enable VLD:
FEM_01
3073 LaMaster 1, FC
Funktionen
LUT_FLC_FORWARDLIGHTING_Y = F020_mit_AFS
C_AFS_ENA - F020_enable
I was curious about enabling option 5AC HBA High Beam Assistant since the vehicle appears to have the KaFAS camera. KaFAS is the Camera Assisted Driver Assistance System / Kameraunterstütztes Fahrerassistenzsystem. The KaFAS camera is utilized by the factory installed options:
- 5AS Active Driving Assistant
- 5AG Lane change warning / lane departure warning
- 8TH Speed limit info
However, HBA requires the presence of the HBA switch on the light controller stalk:
