TOKYO — Carlos Ghosn, one of the auto industry’s most powerful leaders, lost another title on Monday when the board of Mitsubishi Motors removed him as chairman, one week after he was arrested in Tokyo on suspicion of financial misconduct.

Mr. Ghosn, who was stripped of the chairmanship of Nissan last week in a unanimous vote of the board, remains in a Tokyo detention center, where he sees his lawyer for about an hour or so each day. He is being questioned by prosecutors after Nissan said that he underreported his income to Japanese regulators over several years. He has not been charged with any crime.

In a statement on Monday, Osamu Masuko, chief executive of Mitsubishi, said the board had removed Mr. Ghosn because “he lost the trust of Nissan, and he cannot execute his duties as chairman and representative director any longer.”

Mr. Masuko added that if Mr. Ghosn remained as chairman, it could expose Mitsubishi to “reputation risk.”