Headlamp Alignment Control Module: Description and Operation
AHL Control Module (664)
Main task
The task of the AHL control module is to regulate headlamp beam length. The control module ensures that the headlamps are always angled optimally during acceleration, braking and with different loads. The control system has two load angle sensors located at the front and rear axles, respectively.
Type
The control module has a microprocessor with clock, RAM memory and a flashable ROM. An internal bus connects the processor and memories with the I/O unit. The I/O unit is responsible for loading the values from the A/D converter for analogue inputs, digital inputs on the bus and for activating the transistors in the power amplifiers. For a general description of vehicle control modules, see Control modules, general description.
Power supply, ground and bus communication
Pin No. 1 - 20:
Diagram:
