Hmmm...So far, I've discovered two incorrect parts listings in the owner's manual for my new xA. The manual lists the bulb for the storage area (oven) as a "4.9watt double-ended" bulb. That's not right. I took it apart and changed it last night. The bulb is a standard #194 bulb which is a single-ended wedge type bulb. Also, according to the owner's manual, the headlight bulbs are a HB2. While that's not entirely wrong, most people will not find a HB2 listed or available at the store. The bulb is a standard 9003. I bought and installed Silverstars last night, and they are #9003ST. Turns out (according to Sylvania/Osram customer service) the HB2 designates the type of bulb, but the number you need to look for in the store is the 9003. Hope this helps.

 

H4, HB2 and 9003 are all the same bulb type.

 

I see. I didn't know that. Go into an autoparts store or the automotive section of a department store and try to find a HB2. The owner's manual should list the bulbs by the number that people will need to look for. Almost all of the major manufacturers here in the US list that bulb as 9003.

 

here is a link with some more info:

http://www.candlepowerinc.com/pdfs/H4_9003.pdf

 

Wow...everything you ever wanted to know about H4/HB2/9003 headlight bulbs. Thanks! Where were you with this info yesterday?

 

Also worth checking out:

https://www.scionlife.com/forums/viewtopic.php?t=7225

It's got the bulb sizes for the xB, but they're all the same for the xA too. Also has feedback from xA owners about the bulb for the "oven".

 

9003 or H4 bulbs will fit the Scion xA, as they are same as HB2. I believed the HB2 means the housing of the headlight is constructed a little differently compared to H4; however, the bulb spec remains as same.
Also, the 194 bulbs also can be called other model numbers as well...had all the bulbs changed in the xA and wife is very happy