Try taking a picture of a white sheet of paper.
Also, check the camera lens. Some of them come with a little piece of protective plastic. If you leave that on, it can blue (or yellow) with age.
If the white paper isn't shooting as white, try playing with the white balance manually.
Also, make sure you're not shooting under some strange lighting condition. (Even "normal" fluorescent lighting can fool AWB if it's around 6500K - normal daylight bulbs should be closer to 4500K. and an older bulb, on its last legs, can go to 7000K, which really pushes the limits of what the AWB can handle.
Shoot in bright sunlight, on a cloudless day, around noon, at a white sheet of paper (or an "18% grey card" if you have one). AWB should handle that light properly.
(You get the opposite in a room with incandescent light with a dimmer, with the light turned way down. That's not yellowish or orange-ish light, that's red light, and the camera just can't handle it. Aren't eyes amazing cameras - you never notice the color, you just balance automatically.)