A control system for a vehicle includes a first vehicle system including a plurality of components and a controller. The controller monitors diagnostic data for the plurality of components of the first vehicle system and outputs a two-state status indicator for each of the components of the first vehicle system. States of the two-state status indicator include a failing state and a not failing state. A control module is configured to receive the two-state status indicator and the diagnostic data from the first vehicle system and to convert the two-state status indicator into a three-state status indicator. The three-state status indicator includes a pass state, a fail state and an indeterminate state. The control module is further configured to alter an engine operating parameter based on the three-state status indicator.

A method for fault-tolerant coasting control of a powertrain system having an engine and a first energy storage system (ESS) includes receiving a real impedance value of the first ESS from a frequency analyzer device at a calibrated frequency while the engine is running, and comparing the real impedance value to a calibrated impedance. A coasting maneuver is enabled allowing the engine to turn off above a threshold speed when the real impedance value is less than the calibrated impedance. The method may include starting the engine using a second ESS in parallel with the first ESS to exit the coasting maneuver when the real impedance value exceeds the calibrated impedance. Subsequent execution of the coasting maneuver may be prevented as long as the real impedance value exceeds the calibrated impedance. A powertrain system includes the engine, starter motor, rechargeable ESS, frequency analyzer, and controller.

A vehicle power supply system has a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a DC-DC converter, and a controller. In a case where power is supplied to both of a starter and an electrical component from any one of a first battery and a second battery, the controller causes power to be supplied to the electrical component via the DC-DC converter.

A method for fault-tolerant coasting control of a powertrain system having an engine and a first energy storage system (ESS) includes receiving a real impedance value of the first ESS from a frequency analyzer device at a calibrated frequency while the engine is running, and comparing the real impedance value to a calibrated impedance. A coasting maneuver is enabled allowing the engine to turn off above a threshold speed when the real impedance value is less than the calibrated impedance. The method may include starting the engine using a second ESS in parallel with the first ESS to exit the coasting maneuver when the real impedance value exceeds the calibrated impedance. Subsequent execution of the coasting maneuver may be prevented as long as the real impedance value exceeds the calibrated impedance. A powertrain system includes the engine, starter motor, rechargeable ESS, frequency analyzer, and controller.

Systems and methods for starting an engine are described. In one example, engine cranking speed for an engine of a hybrid vehicle is adjusted in response to operating conditions. The engine cranking speed may be reduced when capability of a battery that supplies power to rotate the engine is less than an amount of power to rotate the engine at a higher speed.

A system includes an ultra-capacitor and battery system comprising a battery, an ultra-capacitor, a DC-DC converter, a first temperature sensor to sense a battery temperature, a second temperature sensor to sense an ultra-capacitor temperature and a third temperature sensor to sense a DC-DC converter temperature. An auto stop/start module is configured to selectively stop and restart an engine of a vehicle while an ignition system is ON based on operating parameters. A temperature sensing module communicates with the auto stop/start module and is configured to determine differences between temperatures sensed by the first sensor, the second sensor and the third sensor and to selectively disable the auto stop/start module based on the differences.

A control system for a vehicle includes a first vehicle system including a plurality of components and a controller. The controller monitors diagnostic data for the plurality of components of the first vehicle system and outputs a two-state status indicator for each of the components of the first vehicle system. States of the two-state status indicator include a failing state and a not failing state. A control module is configured to receive the two-state status indicator and the diagnostic data from the first vehicle system and to convert the two-state status indicator into a three-state status indicator. The three-state status indicator includes a pass state, a fail state and an indeterminate state. The control module is further configured to alter an engine operating parameter based on the three-state status indicator.