Headlamp Control Unit, Basic Function - GF82.10-P-9890A

Model all (CAR) 

with code 631 (Static LED headlamps, left-hand traffic) 

Model all (CAR) 

with code 632 (Headlamps, LED, static, right-side traffic) 

Model all (CAR) 

with code 640 (SAE dynamic LED headlamps, right-hand traffic) 

Model all (CAR) 

with code 641 (Dynamic LED headlamps, left-hand traffic) 

Model all (CAR) 

with code 642 (Dynamic LED headlamps, right-hand traffic) 

Location 

The headlamp control units are located on the outer side of the respective front lamp unit.

The headlamp control units are bolted onto the housing of the respective front lamp unit. The headlamp control units are connected to the vehicle-side wiring harness via the front lamp units.

Task 

The headlamp control units are connected to the vehicle's network architecture. It operates in master-slave combination. As the master, the left headlamp control unit synchronizes the right headlamp control unit.

Dynamic LED headlamp 

The LED headlamps are equipped with LED matrices. These are equipped with several LEDs that can be actuated independently of one other. Depending on which LEDs are actuated, the shape and, depending on the version of the LED headlamps, the intensity of the light cone can be influenced.

As of market launch model 247, the headlamp control units assume the control of all light functions.

The headlamp control units actuate the following functions:

• Position lights
• Turn signal lamp
• High beams and headlamp flasher output
• Automatic headlamp range control (HRA) (left headlamp control unit only) (except Canada version and USA version with static LED headlamps, right-hand traffic)
• Variable light distribution (dynamic LED headlamps)
  • Town light
  • Country light and curve illumination
  • Motorway light
  • Enhanced fog light function (depending on the version of the LED headlamps)
• Cornering light (dynamic LED headlamps)
• Thermal management (temperature monitoring)

On model 167, 177, the headlamp control units have supported variable light distribution via the headlamp range adjustment. As of market launch model 247, the headlamp control units completely control variable light distribution.

To implement the exterior lighting functions, the headlamp control units process, among others, the following information:

• Variant coding
• Circuit status
• Engine running signal (vehicles with combustion engine)
• Powertrain operational signal
• Vehicle level
• Temperatures in the front lamp units
• Light function request
• Freeze frame data (dynamic LED headlamps)
• Object information for automatic high beam (Dynamic LED headlamp) (as of model 247 market launch)

The headlamp control units process these input factors and send, among others, the following information:

• Requests for high beam light distribution (dynamic LED headlamps)
• Light distribution status (dynamic LED headlamps)
• Status of light functions
• Show display messages request