LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Volvo >> 2002 >> S80 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 35 (Control Modules - Design And Function - 2 Of 4) >> GDL Bulbs (2005-2009) >> Design >> Ballast
April 5, 2026: LEMON Manuals is launched! Read the announcement.

GDL Bulbs (2005-2009): Design: Ballast

WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2009 Volvo S60, 2008 Volvo S60, 2007 Volvo S60, 2006 Volvo S60, and 2005 Volvo S60. However, it is still accessible from the selected car via links, so may be relevant.

An electronic ballast is connected to each headlight. The ballast serves as a voltage regulator and generates alternating current (AC).

Primary tasks: 

  1. Light the bulb.
  2. Regulate light during operation.

A initial voltage of about 24,000 V for a very brief period (less than 1 ms) is required to light the bulb.

The ballast transforms the vehicle's 12 V (DC) to 1000 V (AC).

The high voltage contact amplifies the voltage an addition 25 times.

Once the bulb has been lit, voltage is regulated down to about 100 V, which is required to keep the bulb lit.

Power consumption: 10 W.