Vehicle Engineers reports, 4WD Modification rules, whats allowed, what not...

[Clunk]

Low beam turn off when highs are on.. So that is not correct.

No they dont

[LostBenji]

No they dont

Incorrect, most do. Too much current draw with both lit on the common negative wire and also too much heat to dissipate in the lamp assembly. Look at car next time with blown high, it will only have the park lamp (if not blown too).
Big GU is correct in the technical respect.

[Clunk]

Incorrect, most do. Too much current draw with both lit on the common negative wire and also too much heat to dissipate in the lamp assembly. Look at car next time with blown high, it will only have the park lamp (if not blown too).
Big GU is correct in the technical respect.

well bugger be sideways, you learn something new everyday....... although my park (side) lights are separate to the main lights.

So why is it that with HID headlights, when you first turn the lights on low beam, they take a while to get up to brightness, but when you switch to high beams, the brightness is instant?

[lhurley]

well bugger be sideways, you learn something new everyday....... although my park (side) lights are separate to the main lights.

So why is it that with HID headlights, when you first turn the lights on low beam, they take a while to get up to brightness, but when you switch to high beams, the brightness is instant?

A HID (High Intensity Discharge) light works by heating the gas in the bulb to create the light. The "getting to brightness is them warming up to operating temperature.
When you flick on high beam (on a legal projector lens) there is a little blade that flicks down allowing full light through the projector. Normally the blade blocks a portion of the light, thus giving you "low beam" and that nice straight cut off line.

[Winnie]

A HID (High Intensity Discharge) light works by heating the gas in the bulb to create the light. The "getting to brightness is them warming up to operating temperature.
When you flick on high beam (on a legal projector lens) there is a little blade that flicks down allowing full light through the projector. Normally the blade blocks a portion of the light, thus giving you "low beam" and that nice straight cut off line.

That's not the case though on a HID lamp that you see installed in a regular light reflector though.