A multi-mode powertrain system is described, and includes an internal combustion engine having stop/start capability. A method for controlling the multi-mode powertrain system includes circulating coolant to a heater core via an engine fluidic circuit that includes a water jacket of the internal combustion engine when temperature of the coolant is less than an engine fluidic circuit upper temperature threshold and the engine is in an ON state. Coolant is circulated to the heater core via a bypass fluidic circuit that excludes the water jacket of the internal combustion engine when temperature of the coolant is greater than a bypass fluidic circuit lower temperature threshold when the engine is in an OFF state.

A hybrid vehicle includes: an engine; a motor; a drive system battery connected to a drive system power line; an auxiliary system battery connected to an auxiliary system power line; a bidirectional power converter configured to step down power on the drive system power line to supply the stepped-down power to the auxiliary system power line, and configured to boost power on the auxiliary system power line to supply the boosted power to the drive system power line; and a control device. The control device is configured to, upon a cold start in which the engine is started, control the engine, the motor, and the bidirectional power converter to cause the motor to crank the engine while causing the bidirectional power converter to boost the power on the auxiliary system power line to supply the boosted power to the drive system power line.

A hybrid drive device includes an internal combustion engine, an electric machine and an impulse start module which comprises two clutches and a flywheel mass. A method for operating the hybrid device includes opening the first clutch of the impulse-start module and establishing a start-up requirement for the internal-combustion engine. The method also includes closing the first clutch with the second clutch in an open or closed position for a start of the internal-combustion engine.

A vehicle drive system for a vehicle including a first prime mover, a first prime mover driven transmission, and a rechargeable power source can be configured for reduced fuel consumption at idle. The vehicle drive system includes an electric motor in direct or indirect mechanical communication with the first prime mover. The control system causes fuel to be eliminated to the first prime mover while the vehicle is stopped and causes the electric motor to rotate the first prime mover at a speed, thereby reducing fuel consumption at idle for the vehicle.

A controller for a vehicle is configured to execute a lubricating oil degradation degree acquisition process that calculates a degradation degree of a lubricating oil that lubricates an internal combustion engine, a battery degradation degree acquisition process that calculates a degradation degree of a battery, and an oil change time calculation process that calculates an oil change time for the lubricating oil from the degradation degree of the lubricating oil and the degradation degree of the battery. The oil change time calculation process includes calculating the oil change time so as to become earlier as the degradation degree of the battery increases.

Methods and systems for evacuating lubricant from an area of an axle are described. The lubricant may be evacuated away from one or more clutches during low temperatures so that a clutch may be engaged while having to displace less lubricant to engage the clutch. In one example, an electric machine may be rotated to evacuate lubricant away from the clutch.

Methods and systems for evacuating lubricant from an area of an axle are described. The lubricant may be evacuated away from one or more clutches during low temperatures so that a clutch may be engaged while having to displace less lubricant to engage the clutch. In one example, an electric machine may be rotated to evacuate lubricant away from the clutch.

A method of controlling a hybrid vehicle including an engine, a motor, a starter, a friction engagement element provided between the engine and the motor, and a mechanical oil pump which is driven by the motor and supplies oil to the friction engagement element, is provided. When the friction engagement element is in a disengaged state, a first traveling mode using the motor is performed. When it is in an engaged state, a second traveling mode at least using the engine is performed. The method includes, when the first traveling mode is unperformable, starting the engine by the starter to perform the second traveling mode, activating the motor and performing a hydraulic pressure control for shifting the friction engagement element from the disengaged to engaged state after starting the engine. The hydraulic pressure control uses at least the hydraulic pressure from the mechanical oil pump driven by activating the motor.

A method of controlling a hybrid vehicle including an engine, a motor, a starter, a friction engagement element provided between the engine and the motor, and a mechanical oil pump which is driven by the motor and supplies oil to the friction engagement element, is provided. When the friction engagement element is in a disengaged state, a first traveling mode using the motor is performed. When it is in an engaged state, a second traveling mode at least using the engine is performed. The method includes, when the first traveling mode is unperformable, starting the engine by the starter to perform the second traveling mode, activating the motor and performing a hydraulic pressure control for shifting the friction engagement element from the disengaged to engaged state after starting the engine. The hydraulic pressure control uses at least the hydraulic pressure from the mechanical oil pump driven by activating the motor.

A vehicle includes a gear mechanism connected to a driving wheel; a traveling electric motor configured to exchange heat with a heat exchange medium shared by the gear mechanism and output motive power to the driving wheel via the gear mechanism; and a controller configured to change an operating point of the traveling electric motor to a stronger field side rather than a maximum efficiency point in a case that a temperature of the heat exchange medium is less than a predetermined temperature.