"During regularly scheduled testing of the ship's emergency diesel generator, a malfunction occurred, " Carnival said in a statement.

CNN: STORY HIGHLIGHTS

Carnival said the ship's emergency diesel generator failed, but the cruise line disputed notions of a widespread system failure.

CNN: STORY HIGHLIGHTS

In a statement, Carnival said the ship's emergency diesel generator failed.

CNN: STORY HIGHLIGHTS

In 2007 an emergency diesel generator began smoking during testing.

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