Headlamp range adjustment (HRA) headlamp function - GF82.10-P-1001TT

MODEL 211.0 /2 up to 31.5.06 with CODE (614) Bi-xenon headlamp unit with CODE (615) Bi-xenon headlamp unit with integrated curve illumination except CODE (494) USA version except CODE (498) Japan version

MODEL 211.0 /2 up to 30.6.06 with CODE (614) Bi-xenon headlamp unit with CODE (615) Bi-xenon headlamp unit with integrated curve illumination with CODE (494) USA version with CODE (498) Japan version

Fig 1: Locating Headlamp Range Adjustment Components

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Shown on model 211.0 without code (489) Airmatic (semi-active air suspension)

Headlamp range adjustment is prescribed by law to prevent xenon headlamps dazzling oncoming traffic.

The headlamp range control automatically maintains the inclination angle of the headlamps within the legally defined limits regardless of the vehicle load.

Function requirements

Circuit 15 ON
Terminal 61 ON

Function

On model 211.0 without code (489) Airmatic (semi-active air suspension) the data of the front axle level sensor (B22/2) and the rear axle level sensor (B22/3) are read in directly by the headlamp range adjustment control unit (N71).

On model 211.2 without code (489) Airmatic (semi-active air suspension) the data of the front axle level sensor (B22/2) are read in directly by the headlamp range adjustment control unit (N71). The data of the rear axle level sensor (B22/3) are read in by the rear axle level control system control unit (N97) and transmitted to the headlamp range adjustment control unit (N71) via CAN Class C.

On model 211 with code (489) Airmatic (semi-active air suspension) the data of the left front level sensor (B22/8), right front level sensor (B22/9), and rear axle (B22/3) are read in by the AIRmatic with ADS control unit (N51) and transmitted to the headlamp range adjustment control unit (N71) via CAN Class C.

The headlamp range adjustment control unit (N71) forwards the evaluated data via the HRA [LWR] bus to the driver-side SAM control unit with fuse and relay module (N10/1). The HRA [LWR] power module (E1n3) on the left front lamp unit (E1) actuates the front left headlamp range adjustment motor (E1m1), the HRA [LWR] power module (E2n3) on the front right lamp unit (E2) actuate the right headlamp range adjustment motor (E2m1). The headlamp range adjustment motors (E1m1, E2m1) relay their respective position to the HRA [LWR] power module (E1n3, E2n3) via internal potentiometers.

Driver-side SAM control unit with fuse and relay module, location/task/design	GF54.21-P-4109T
Headlamp leveling system motor, location/task/design/function	GF82.10-P-2101TT
Headlamp leveling system control unit, location/task/design/function	GF82.10-P-2102T
HRA [LWR] power module location/task	GF82.10-P-2107T