Patent ID: 6842682

Claim:
A driving force distribution control method for a four-wheel-drive vehicle having a torque transmission device configured to distribute torque transmitted from an engine to a first set of wheels directly driven and to a second set of wheels driven therethrough, the control method comprising the steps of: detecting throttle-opening of the engine; obtaining a first torque command which depends on the throttle-opening; detecting a rotational speed difference between the first set of wheels and the second set of wheels; obtaining a second torque command which depends on the rotational speed difference; controlling the torque transmission device based on the first torque command and the second torque command so as to transmit the driving force to the second set of wheels according to the throttle-opening and the rotational speed difference; and monitoring a signal which corresponds to the throttle-opening, wherein when the signal is judged being abnormal, the first torque command is ignored so that the torque transmission device is controlled based on the second torque command.