Abstract: A method for controlling a hybrid powertrain includes the following steps: (a) receiving, via a control module, a torque request; (b) commanding, via the control module, the first clutch of an automatic transmission to shift to a disengaged position in response to the torque request; (c) commanding, via the control module, an electric motor-generator to transmit torque to an internal combustion engine until a speed of a second clutch is substantially synchronized with a speed of the internal combustion engine; and (d) commanding, via the control module, the second clutch to shift to the engaged position after the speed of the second clutch is substantially synchronized with the speed of the internal combustion engine. The automatic transmission shifts a transmission speed ratio from an initial speed ratio to a subsequent speed ratio when the second clutch is in the engaged position.

Abstract: A vehicle includes a first axle, a second axle, an engine having a crankshaft, a transmission having an input member that is operatively connected to the crankshaft and an output member that is operatively connected to the first axle, a first motor having a first rotor operatively connected to the crankshaft, a second motor having a second rotor that is operatively connected to the second axle, and a controller being operatively connected to the engine, the first motor, and the second motor. The controller is configured to selectively cause the engine to enter a deceleration fuel cut off mode, cause the transmission input torque to increase to zero, cause the torque of the second motor to decrease as the transmission input torque increases such that the sum of the first axle torque and the second axle torque remains substantially constant as the transmission input torque increases to zero.

Abstract: A vehicle includes a first axle, a second axle, an engine having a crankshaft, a transmission having an input member that is operatively connected to the crankshaft and an output member that is operatively connected to the first axle, a first motor having a first rotor operatively connected to the crankshaft, a second motor having a second rotor that is operatively connected to the second axle, and a controller being operatively connected to the engine, the first motor, and the second motor. The controller is configured to selectively cause the engine to enter a deceleration fuel cut off mode, cause the transmission input torque to increase to zero, cause the torque of the second motor to decrease as the transmission input torque increases such that the sum of the first axle torque and the second axle torque remains substantially constant as the transmission input torque increases to zero.

Abstract: A method for controlling a hybrid powertrain includes the following steps: (a) receiving, via a control module, a torque request; (b) commanding, via the control module, the first clutch of an automatic transmission to shift to a disengaged position in response to the torque request; (c) commanding, via the control module, an electric motor-generator to transmit torque to an internal combustion engine until a speed of a second clutch is substantially synchronized with a speed of the internal combustion engine; and (d) commanding, via the control module, the second clutch to shift to the engaged position after the speed of the second clutch is substantially synchronized with the speed of the internal combustion engine. The automatic transmission shifts a transmission speed ratio from an initial speed ratio to a subsequent speed ratio when the second clutch is in the engaged position.

Abstract: A vehicle includes an internal combustion engine, an engine control module (ECM) programmed to estimate engine torque as a function of throttle request, and a transmission assembly. The transmission assembly includes a plurality of gear sets and clutches, including an offgoing clutch and an oncoming clutch for a power downshift, and a transmission control module (TCM). The TCM includes a processor and memory on which is recorded a shift line for the downshift, and instructions for executing the downshift. The TCM communicates an estimated throttle level at the shift line to the ECM, receives an estimated engine torque for the estimated throttle level at the shift line from the ECM, and decreases offgoing pressure to the offgoing clutch to a threshold pressure level prior to executing the downshift. The TCM then decreases the offgoing clutch pressure to a calibrated pressure at the shift line to execute the downshift.

Abstract: A vehicle includes an internal combustion engine, an engine control module (ECM) programmed to estimate engine torque as a function of throttle request, and a transmission assembly. The transmission assembly includes a plurality of gear sets and clutches, including an offgoing clutch and an oncoming clutch for a power downshift, and a transmission control module (TCM). The TCM includes a processor and memory on which is recorded a shift line for the downshift, and instructions for executing the downshift. The TCM communicates an estimated throttle level at the shift line to the ECM, receives an estimated engine torque for the estimated throttle level at the shift line from the ECM, and decreases offgoing pressure to the offgoing clutch to a threshold pressure level prior to executing the downshift. The TCM then decreases the offgoing clutch pressure to a calibrated pressure at the shift line to execute the downshift.

Abstract: A method for detecting a clutch fault of an automatic transmission includes determining a current clutch energy density of a clutch during a range shift and comparing the current clutch energy density to a first energy density threshold. A diagnostic alert is activated if the current clutch energy density exceeds the first energy density threshold.