The 3181-SC012B2001 OLB3522 control unit is an electronic control unit that controls the xenon headlights of trucks.

Its main function is to provide the electrical power needed for the headlight ballasts, which are the devices that generate the electrical discharge that produces xenon light.

The control unit also manages other functions of the xenon headlights, such as:

• Turning the headlights on and off
• Adjusting the height of the headlights
• Adjusting the light intensity
• The low beam/high beam function
• The automatic headlight switch function

The control unit is an important component of the lighting system of Iveco Stralis and Eurocargo vehicles with xenon headlights. If the control unit fails, the xenon headlights will not function properly or may not turn on at all.

The most common symptoms of a 3181-SC012B2001 control unit failure are:

• The xenon headlights do not turn on
• The xenon headlights turn on but do not emit light
• Xenon headlights emit irregular light
• The height of the headlights is not adjustable
• The intensity of the headlights is not adjustable
• The low beam/high beam function does not work
• The automatic headlight function does not work

If you experience any of these symptoms, it is advisable to have the ECU checked by a qualified mechanic.