Metal Halide Bulb
WARNING: This page is about a different car, the 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Never touch the glass portion or the electrode portion of the bulb because of the high voltage that is generated at those areas is very dangerous.
The metal halide bulb contains xenon gas, mercury and metal halide. See Fig 1.
Operation:
- When high voltage (approximately 20,000 volts) is applied to the electrodes of the metal halide bulb, the xenon gas in the bulb emits light.
- As the temperature in the bulb rises, the mercury evaporates and causes arcs to be discharged.
- As the temperature in the bulb rises even further, the metal halide in the mercury arc separates into metal atoms and iodine atoms.
- The separated metal atoms discharge light, which causes the bulb to emit light.