Hey, my radiator stopped working recently,
"Stopped working recently" isn't very specific. What exactly happened?
Anyway, I bet these two parts are the same. They're the same price. The first site has more information, but the second site claims theirs only works on auto-trans Yarises. Probably just don't use the built-in trans cooler if you have a manual.
You should remember to use only distilled/deionized water when you fill up a radiator, if you're using concentrated antifreeze and not "premixed". Distilled or deionized water is cheap and easy to get so there's no excuse for using tap water, and tap water will cause mineralization problems in the radiator.
