Headlamp Control Module (HCM) (2010-2011): Function: Safety

In the event of a short-circuit on the high tension side the power supply cuts in less than 10 ms
If the high voltage circuit is broken (such as due to an open circuit, defective bulb or no bulb in the lamp socket), during each activation the system attempts to light the lamp for a period of 700 ms. During the period, there is high voltage across the ballast.
Approximate component temperatures during operation: Ballast = 130 °C (266 °F), Lamp holder = 170 °C (338 °F), Bi-Xenon lamp = 400 °C (752 °F).
The glass body of the Bi-Xenon-lamp is filled with different gases and metal vapors which are under pressure. The lamp can explode as it is under gas pressure.

WARNING:

Follow the safety instructions and recommendations in VIDA (Volvo Scan Tool) carefully when working with high voltage.
Use safety goggles when handling the bulb. Risk of explosion
The electrical system must be turned off before starting work.
Risk of burn injury. The components operate at very high temperatures.