An embodiment system for mild hybrid starter and generator (MHSG) failure diagnosis of a mild hybrid vehicle includes a data detection part configured to detect data for determining whether to activate a catalyst, and a controller configured to determine whether there is an MHSG failure using a deviation between a required torque and an actual operating torque of an MHSG after determining whether catalyst activation is needed and whether to start a stage of the MHSG failure diagnosis based on the data detected by the data detection part.

A system and method for modifying the engine pull-up (EPU) logic within a hybrid vehicle based on max motor torque that accounts for the drop or change in available motor torque due to the opening/slipping of a torque converter bypass clutch during engine starts is disclosed. An engine pull-up threshold is determined from max available motor torque at a virtual impeller speed, where the virtual impeller speed is the impeller speed that would result if the torque converter bypass clutch was open/slipping and transferring the same amount of torque.

Systems and methods for starting an engine that may be started via two different electric machines are described. In one example, the method reserves an amount of torque that is based on a torque capability of a belt integrated starter/generator and the engine is started with the reserved torque if engine starting torque is greater than a torque capability of the belt integrated starter/generator.

A control device prevents damage due to backward rotation of a rotary engine and prevents misjudgment of backward rotation of the rotary engine. The control device for a rotary engine includes a motor mechanically connected to the shaft of the rotary engine, a controller (a motor ECU) that performs energization control of the motor to start the rotary engine by driving the motor, and a sensor (such as a motor rotation sensor). When starting the rotary engine, the controller stops energization to the motor based on an electric signal from the sensor when the shaft of the rotary engine rotates backward a predetermined angle or more, and then the shaft of the rotary engine continues to rotate backward for a predetermined time.

A method for operating a vehicle that includes a driveline disconnect clutch is described. In one example, the method adjusts torque of an electric machine in response to a estimated torque capacity of the driveline disconnect clutch. The estimated torque capacity of the driveline disconnect clutch is based on a combined inertia of a dual mass flywheel and the driveline disconnect clutch.

A starter assembly includes a housing defining an interior, a rotatable pinion gear wherein the rotatable pinion gear extends exteriorly of the housing and operably coupling to a combustion engine, a torque sensor providing a torque output indicative of a torque experienced by the pinion gear, and a controller module configured operate a starting sequence for the starter assembly.

Systems and methods for operating a hybrid vehicle are described. In one example, a torque reserve for starting an engine via an electric machine is adjusted responsive to vehicle operating conditions. The torque reserve may set aside a portion of torque that an electric machine may produce for cranking and starting an engine.

Systems and methods for starting an engine that may be started via an electric machine and a driveline disconnect clutch are described. In one example, the method estimates a maximum motor propulsive torque during engine starting. The maximum motor propulsive torque may be based on an estimated speed that a torque converter impeller speed will be when an engine cranking period ends.

A control unit is provided for a vehicle having an internal combustion engine with a shaft, which can be coupled to an electric machine or decoupled from the electric machine. The control unit is designed to couple the electric machine to the internal combustion engine during an engine stop of the internal combustion engine. The control unit causes the electric machine to guide the shaft of the internal combustion engine. The control unit determines that a speed of the guided shaft is equal to or less than a speed threshold value and, in response thereto, decouples the electric machine from the internal combustion engine, such that the internal combustion engine stops without being guided by the electric machine.

An idling-stop control apparatus includes an idling-stop controller and an auxiliary-machine controller. The idling-stop controller is configured to automatically stop an engine to cause the engine to be in a state in which idling is stopped in a case where a predetermined condition for stopping idling is satisfied and configured to automatically restart the engine in a case where a predetermined condition for restarting the engine is satisfied. The auxiliary-machine controller is configured to control a drive state of an auxiliary machine that is to be driven by the engine. The auxiliary-machine controller is configured to control the drive state of the auxiliary machine that is driven by the engine such that, in a case where the engine is automatically restarted from the state in which idling is stopped by the idling-stop controller, a time differential value of an engine speed of the engine is constant.