Abstract: A distributed on-board diagnostic (OBD) architecture for a control system of a vehicle includes a plurality of control modules that are in communication with one another and a designated master OBD control module that is one of the plurality of control modules. The master OBD control module performs functions that a remainder of the plurality of control modules are incapable of performing including at least one of arbitrating a malfunction indicator lamp (MIL) state, arbitrating and storing OBD freeze frame data and determining OBD status flags of the remainder of the plurality of control modules.

Abstract: A diagnostic system for a vehicle includes a first sensor that generates a first status signal, which is indicative of an engine speed of an engine. A second sensor generates a second status signal that is indicative of an actual accessory speed of an accessory. The accessory is coupled to the engine via a belt system. A control module determines an expected accessory speed based on the engine speed and determines a residual accessory speed based on the expected and actual accessory speeds. The control module also detects a fault in the belt system based on the residual accessory speed.

Abstract: A method and apparatus to monitor operation of an electrically-actuated hydraulic pump selectively operative to supply pressurized fluid to a hydraulic circuit for a transmission device operably connected to an internal combustion engine of a vehicle includes monitoring vehicle operation and passively and intrusively monitoring hydraulic circuit pressure. The hydraulic pump is functioning properly when the monitored pressure in the hydraulic circuit exceeds a threshold. A fault related to the hydraulic circuit is identified when the monitored pressure in the hydraulic circuit does not exceed the threshold.

Abstract: A power distribution system for a hybrid vehicle having an engine is disclosed. The power distribution system includes an electric motor/generator, a vehicle accessory drive system comprising a first accessory, and a power distribution apparatus. The power distribution apparatus includes a first power transfer member comprising a first shaft, the first shaft being configured to transfer power to the engine and from the engine. The power distribution apparatus further includes a second power transfer member comprising a second shaft, the second shaft being configured to transfer power to the motor/generator and from the motor/generator. The power distribution apparatus further includes a third power transfer member comprising a third shaft, the third shaft being configured to transfer power to the accessory drive system to drive the first accessory. The power distribution apparatus further includes a first clutch and a second clutch.

Abstract: The invention comprises a method and apparatus to monitor operation of an electrically-actuated hydraulic pump selectively operative to supply pressurized fluid to a hydraulic circuit for a transmission device operably connected to an internal combustion engine of a vehicle. It includes monitoring vehicle operation and passively and intrusively monitoring hydraulic circuit pressure. The hydraulic pump is functioning properly when the monitored pressure in the hydraulic circuit exceeds a threshold. A fault related to the hydraulic circuit is identified when the monitored pressure in the hydraulic circuit does not exceed the threshold.

Abstract: A diagnostic system for a vehicle includes a first sensor that generates a first status signal, which is indicative of an engine speed of an engine. A second sensor generates a second status signal that is indicative of an actual accessory speed of an accessory. The accessory is coupled to the engine via a belt system. A control module determines an expected accessory speed based on the engine speed and determines a residual accessory speed based on the expected and actual accessory speeds. The control module also detects a fault in the belt system based on the residual accessory speed.

Abstract: A distributed on-board diagnostic (OBD) architecture for a control system of a vehicle includes a plurality of control modules that are in communication with one another and a designated master OBD control module that is one of the plurality of control modules. The master OBD control module performs functions that a remainder of the plurality of control modules are incapable of performing including at least one of arbitrating a malfunction indicator lamp (MIL) state, arbitrating and storing OBD freeze frame data and determining OBD status flags of the remainder of the plurality of control modules.