A vehicle control device for controlling a vehicle with a frictional engagement element provided between a drive source and drive wheels includes a first determination unit configured to determine whether or not a signal of an inhibitor switch indicates a traveling position, a second determination unit configured to determine whether or not an oil path communicating with the frictional engagement element is in a drain state, a temperature estimation unit configured to estimate temperature of the frictional engagement element, and a temperature estimation prohibition unit configured to prohibit temperature estimation of the frictional engagement element by the temperature estimation unit when the signal of the inhibitor switch indicates the traveling position and the oil path is in the drain state.

Methods and systems are provided for controlling and diagnosing one or more clutches in a transmission. In one example, a method for operation of a vehicle system is provided that includes at a diagnostic controller or processing unit independent from a driveline controller or processing unit, respectively, determining an engagement state of a clutch in a transmission of the vehicle system, wherein the engagement state is selected from a group of three or more clutch engagement states. The method further includes identifying an unauthorized clutch state based on the engagement state of the clutch and a speed of the vehicle and responsive to the identification of the unauthorized clutch state, operating the vehicle system in a fault state.

One vehicle wheel is disconnected from a differential while the vehicle is in a front wheel drive mode. A controller checks for a malfunction of the differential while the vehicle is in the front wheel drive mode and in response to a request to enter an all wheel drive mode. If speeds of the other vehicle wheel and the differential input indicate that the malfunction is present, the all wheel drive mode is disabled and the driver is informed. If fluid temperature indicates a risk of the malfunction, all wheel drive mode is temporarily disabled and the driver is informed. If the temperature condition continues to be present for a predetermined duration, the all wheel drive mode is disabled.

Methods and systems are provided for controlling and diagnosing one or more clutches in a transmission. In one example, a method for operation of a vehicle system is provided that includes at a diagnostic controller or processing unit independent from a driveline controller or processing unit, respectively, determining an engagement state of a clutch in a transmission of the vehicle system, wherein the engagement state is selected from a group of three or more clutch engagement states. The method further includes identifying an unauthorized clutch state based on the engagement state of the clutch and a speed of the vehicle and responsive to the identification of the unauthorized clutch state, operating the vehicle system in a fault state.

A control device for a lock-up clutch includes a control unit, an abnormality determination unit, a release control unit and a prohibition unit. The control unit is configured to control an engagement state of a lock-up clutch, and to perform a slip lock-up control by performing a feedback control of an engagement hydraulic pressure to be a first slip amount during coasting. The abnormality determination unit is configured to determine an abnormality when a state continues with a slip amount being equal to or greater than a second slip amount. The release control unit is configured to release the lock-up clutch when the abnormality is determined. The prohibition unit is configured to allow the control unit to raise the engagement hydraulic pressure by a prescribed pressure, and to prohibit determination by the abnormality determination unit, when the transmission ratio is downshifted during coasting while the slip lock-up control is performed.

A control device for a lock-up clutch includes a control unit, an abnormality determination unit, a release control unit and a prohibition unit. The control unit is configured to control an engagement state of a lock-up clutch, and to perform a slip lock-up control by performing a feedback control of an engagement hydraulic pressure to be a first slip amount during coasting. The abnormality determination unit is configured to determine an abnormality when a state continues with a slip amount being equal to or greater than a second slip amount. The release control unit is configured to release the lock-up clutch when the abnormality is determined. The prohibition unit is configured to allow the control unit to raise the engagement hydraulic pressure by a prescribed pressure, and to prohibit determination by the abnormality determination unit, when the transmission ratio is downshifted during coasting while the slip lock-up control is performed.

A powertrain including a prime mover and an electronically controllable clutch. The powertrain structured selectably engages the clutch to provide power from the prime mover to drive one or more ground contacting wheels and to selectably disengage the clutch to decouple with one or more ground contacting wheels. The electronic control system operatively communicates with the prime mover and the electronically controllable clutch, and uses a predictive cruise control (PCC) controller and an idle coast management (ICM) controller, to control vehicle speed during concurrent operation of the PCC controller and the ICM controller.

A powertrain including a prime mover and an electronically controllable clutch. The powertrain structured selectably engages the clutch to provide power from the prime mover to drive one or more ground contacting wheels and to selectably disengage the clutch to decouple with one or more ground contacting wheels. The electronic control system operatively communicates with the prime mover and the electronically controllable clutch, and uses a predictive cruise control (PCC) controller and an idle coast management (ICM) controller, to control vehicle speed during concurrent operation of the PCC controller and the ICM controller.

One vehicle wheel is disconnected from a differential while the vehicle is in a front wheel drive mode. A controller checks for a malfunction of the differential while the vehicle is in the front wheel drive mode and in response to a request to enter an all wheel drive mode. If speeds of the other vehicle wheel and the differential input indicate that the malfunction is present, the all wheel drive mode is disabled and the driver is informed. If fluid temperature indicates a risk of the malfunction, all wheel drive mode is temporarily disabled and the driver is informed. If the temperature condition continues to be present for a predetermined duration, the all wheel drive mode is disabled.