[johnej]

I realize that the low beams are hid, are the high beams hid also, if not why?

 

[hip]

I realize that the low beams are hid, are the high beams hid also, if not why?

One word... Cost
Just like everything else, when technology is new, its expensive. Eventually costs will come down as more cars begin to adopt them. Right now, only a handful of cars are using high beam HIDs.

 

[kiteboy]

Also, HID's require a second or two to light up. Therefore, conventional lens assemblies can't be used for flashing hi-beams. The solution many manufacturers take is to make the hi-beams always-on and install louvres to cover and uncover the lights quickly. This further adds to the cost. Headlights with both hi and low-beam HID's are often called bi-xenon.

I think it's a reasonable trade-off to use conventional halogen hi-beams since they're on so little anyways.

 

[Altersys]

The TL uses bi xenons with no halogen backup for the hi flash. The turnon time is fast enough for flashing.

-Alt