Do you have more of a history on this one? Has it been under your care for a while or did you inherit it from someplace?
Something is killing chlorophyll...or preventing it from forming. I think there are chemical treatments some growers do to force this kind of "unusual variegation" to make the succulent more exotic and thus a more desirable purchase for some. The stems on this one are green. Sunburn usually looks more yellow than white. If this is a natural variagated variety, it still might be sun burn. I tend to doubt it though. You don't mention where you are an how much sun you get.
Were it mine, I'd snap off a lot of those branches that have no end growth. Any of those twigs that are brown/shriveled...snap those off at/past the first node after the branch begins. If the branches and remaining leaves are turgid (they look it), don't worry about water until you see fresh growth. A good way to decide when to water jade or p. afra is to feel the stems/leaves. If they are turgid...feel stiff...don't worry about water. When they feel spungy/soft, then it's time to water. I usually water my jade once or twice a winter...much more often during active growth...too often for most people! But, when they are actively growing they are better able to fight off rot.
If it is in full sun for more than an hour or 3, you might shade it until the green returns. If it is getting less than 2 hours of full sun, I'd just be patient with it. Once green starts to return, you can increase sun again.