Hid headlights and high beams

The Prius has a separate 9005 halogen highbeam bulb. The lowbeam bulbs are either LED or H11 Halogen Bulbs, depending on your trim level.

Regarding your other car, you really shouldn't put HIDs in reflector type lights, unless they were designed for them.

 

No. your

No your Gen III low beams use a projector that works OK with a 35 watt kit.

 

Just so you know, there are very few reflectors in the world that allow for aiming with HID bulbs and halogen bulbs without an adverse effect. The overflow of light projecting upwards is more than it should be unless you aim the headlights severely towards the ground which is more dangerous for you, not being able to see ahead. This is for the GenII Prius.

For the GenIII prius, you have projectors for halogen bulbs. This is even worse because it already has a focus and a cutoff designed to work with a certain amount of lumens. But there is also a squirrel finder that just lets a certain amount of light go upwards. This percentage of light in a discrete quantity is "normal" with halogen bulbs. When you go with HID lights the overall absolute amount of light increases, the percentage stays the same, therefore the discrete quantity of light going through the squirrel finder is higher. That's just simple maths.

To remedy this, cover up part of the squirrel finder to lower the percentage thereby hopefully making the absolute quantity of lumens equal (halogen original squirrel finder lumens vs. HID modified/covered squirrel finder lumens). Or the better way, just put in HID projectors. The halogen projectors in the Prius GenIII aren't bad, but you are still blinding drivers even though it doesn't look like it. A piece of tape over the hole with some ninja hand movements is easy enough if you want a cheap and easy fix.

To visualize what I am saying look below (Not my photos, just examples pull from the interwebs):

This is the metal plate inside a projector housing. You see the large cutout, that's the projector cutoff line. That's what gives it the shape. You can even see the little "Z" notch in the middle of the otherwise flat lines, the "step". Now look at the slot below the step, that little cutout. That's the squirrel finder. For a halogen projector with HID bulbs that hole should be decreased in size, or just completely covered.


Here is an unrelated image showing the squirrel finder outputs. Even if you aim the lights properly with a good cutoff with the intentions of not blinding people, that purposefully thrown upward light is not fixable.