The US Supreme Court last month cleared the way for the extradition of Michael Taylor and his son Peter after a months-long legal battle. They arrived in Japan on Tuesday.
The Tokyo district court approved a request by prosecutors to keep the two in custody until March 12, the Kyodo news agency said. They will be held and questioned at the Tokyo Detention House.
The outlet cited legal sources as saying that the Americans, aged 28 and 60, likely faced a suspended sentence, although a senior prosecutor said that a jail term was not ruled out. They may serve it in the US under the Japanese law.
The suspects are accused of having smuggled Ghosn out of his home in Tokyo in a musical instrument case. A private jet flew him to Turkey and then to his childhood home in Lebanon. Ghosn, who was arrested on charges of financial wrongdoing, said he had escaped political persecution.