Abstract: A method is disclosed for detecting ground faults in a communications system. The method includes measuring a predetermined number of voltage points; determining if the measured voltage points represent recessive or dominant bits; identifying which of the predetermined number of voltage points represent inter-frame bits and which represent frame data bits based on whether the measured voltage points are recessive or dominant; calculating a maximum average voltage for the inter-frame bits; calculating an average frame voltage for all dominant bits within a frame; determining a high average dominant voltage count based on a number of frames for which the average frame voltage is greater than a high voltage threshold; and determining if a ground fault exists based on the average frame voltage and the high average dominant voltage count.

Abstract: A method diagnoses a no-start condition in a powertrain having an engine and a starter system operable for starting the engine. The starter system includes a battery, solenoid relay, starter solenoid, and starter motor. The method includes recording starter data over a calibrated sampling duration in response to a requested start event when the solenoid relay is enabled, including a cranking voltage and engine speed. If no battery current sensor is used, the method derives a resistance ratio using an open-circuit voltage and a minimum cranking voltage of the battery. When such a sensor is used, the method derives a battery and starter resistance. A fault mode of the starter system is then identified via a controller using the starter data and either the resistance ratio or the battery and starter resistances. A control action executes that corresponds to the identified fault mode.

Abstract: A distributed vehicle health management system includes a vehicle-based diagnostic processor executing diagnostic routines in a vehicle. The diagnostic routines generate diagnostic data. A processor-based device executes advanced vehicle health management routines. The processor-based device determines a state of health of a component as a function of the diagnostic data. A telematics device communicates at least one of state of health data and diagnostic data from the vehicle. A remote entity disposed remotely from the vehicle. The remote entity receives data via the telematics device, the data being a selective subset of data output from at least one of the vehicle-based processor and processor-based device. The remote entity executes calibration routines as a function of the data received by the vehicle for calibrating at least one of the diagnostic routines and health management routines.

Abstract: A controller area network (CAN) includes a CAN bus having a CAN-H wire, a CAN-L wire, and a pair of CAN bus terminators located at opposite ends of the CAN bus. The CAN further includes a plurality of nodes including controllers wherein at least one of the controllers is a monitoring controller. The monitoring controller includes a CAN monitoring routine for detecting a wire short fault in the CAN bus and its location.

Abstract: A controller area network (CAN) includes a CAN bus having a CAN-H wire, a CAN-L wire, and a pair of CAN bus terminators located at opposite ends of the CAN bus. The CAN further includes a plurality of nodes including controllers wherein at least one of the controllers is a monitoring controller. The monitoring controller includes a detection control routine for isolating faults on the CAN bus including measuring a CAN-H wire voltage, measuring a CAN-L wire voltage, and isolating a short fault based upon the CAN-H wire voltage and the CAN-L wire voltage.

Abstract: A distributed vehicle health management system includes a vehicle-based diagnostic processor executing diagnostic routines in a vehicle. The diagnostic routines generate diagnostic data. A processor-based device executes advanced vehicle health management routines. The processor-based device determines a state of health of a component as a function of the diagnostic data. A telematics device communicates at least one of state of health data and diagnostic data from the vehicle. A remote entity disposed remotely from the vehicle. The remote entity receives data via the telematics device, the data being a selective subset of data output from at least one of the vehicle-based processor and processor-based device. The remote entity executes calibration routines as a function of the data received by the vehicle for calibrating at least one of the diagnostic routines and health management routines.

Abstract: A method of detecting a ground fault in a faulty electronic control unit. A ground fault detection technique executed by a processor is enabled. The processor determines a message count for each respective electronic control unit transmitted during a ground offset condition over a predetermined time period. The message count includes messages communicated within a communication bus having a measured voltage at least a predetermined voltage value above an expected voltage value. The message counts for each respective electronic control unit are normalized. The faulty electronic control unit is identified as a function of the normalized message counts. A fault signal is output to identify the fault electronic control unit.

Abstract: A method for diagnosing a no-start fault of a vehicle push-button start system including a push-button switch, where the system starts a vehicle engine if the switch is pressed and a vehicle brake is applied. The method includes detecting that a no engine crank condition has occurred if the switch is pressed and the brake is applied, and if so, performs a no crank diagnosis. The method also includes determining that a starter control relay has not been enabled after the system is in a crank power mode, and if so, performs a starter not-enabled diagnosis. The method also includes determining that the starter control relay has been disabled before the engine is running, and if so, performs a start disable diagnosis. The method also includes determining that the engine has stalled within some minimum time after it has successfully been started, and if so, performs an engine stall diagnosis.

Abstract: A system and method for determining when to reset a controller in response to a bus off state. The method includes determining that the controller has entered a first bus off state and immediately resetting the controller. The method further includes setting a reset timer in response to the controller being reset, determining whether the controller has entered a subsequent bus off state, and determining whether a reset time. The method immediately resets the controller in response to the subsequent bus off state if the reset time is greater than the first predetermined time interval, and resets the controller in response to the subsequent bus off state after a second predetermined time interval has elapsed if the reset time is less than the first predetermined time interval.

Abstract: A controller area network (CAN) includes a CAN bus with a CAN-H wire, a CAN-L wire, a pair of CAN bus terminators located at opposite ends of the CAN bus, each terminator having a corresponding known terminator resistance value, a plurality of nodes including controllers wherein at least one of said controllers is a monitoring controller. The monitoring controller includes a detection control routine for detecting the presence of a wire-open fault on the CAN bus, including determining a CAN bus resistance, and determining a wire-open fault on the CAN bus based upon the determined CAN bus resistance and the terminator resistance values.

Abstract: A controller area network (CAN) has a plurality of CAN elements including a communication bus and a plurality of controllers. A method for monitoring the CAN includes detecting occurrences of a first short-lived fault and a second short-lived fault within a predefined time window. A first fault set including at least one inactive controller associated with the first short-lived fault and a second fault set including at least one inactive controller associated with the second short-lived fault are identified. An intermittent fault is located in the CAN based upon the first and second fault sets.

Abstract: A method for monitoring communications among a plurality of controllers signally linked to a communication bus of a controller area network includes monitoring bus communications including determining bus error counts for a plurality of execution cycles. When a bus error count associated with message transmission from one of the controllers exceeds a predetermined threshold, the one of the controllers is prohibited from communicating on the communications bus for a predetermined period of time and is included in a subset of candidate fault-active controllers. Any of the plurality of controllers included within the subset of candidate fault-active controllers that successfully transmits a message is removed from the subset of candidate fault-active controllers. A fault-active controller is isolated based upon the subset of candidate fault-active controllers and the bus error counts.

Abstract: A method is disclosed for detecting ground faults in a communications system. The method includes measuring a predetermined number of voltage points; determining if the measured voltage points represent recessive or dominant bits; identifying which of the predetermined number of voltage points represent inter-frame bits and which represent frame data bits based on whether the measured voltage points are recessive or dominant; calculating a maximum average voltage for the inter-frame bits; calculating an average frame voltage for all dominant bits within a frame; determining a high average dominant voltage count based on a number of frames for which the average frame voltage is greater than a high voltage threshold; and determining if a ground fault exists based on the average frame voltage and the high average dominant voltage count.

Abstract: A controller area network (CAN) includes a plurality of CAN elements comprising a communication bus and a plurality of controllers. A method for monitoring includes periodically determining vectors wherein each vector includes inactive ones of the controllers detected during a filtering window. Contents of the periodically determined vectors are time-filtered to determine a fault record vector. A fault on the CAN is isolated by comparing the fault record vector and a fault signature vector determined based upon a network topology for the CAN.

Abstract: A method for monitoring controller area network (CAN) on a mobile system includes identifying links and associated nodes between all the nodes of the CAN, and ranking all the links according to their order of connection to the monitoring controller, including assigning lower ranks to ones of the links proximal to the monitoring controller and assigning higher ranks to ones of the links distal to the monitoring controller. For each of said links, the associated node distal to the monitor is identified. The on-board monitoring controller determines a fault signature for each of the links starting with the link having the highest ranking, said fault signature comprising identified ones of the associated nodes distal to the monitor for each of the corresponding links.

Abstract: A controller area network (CAN) includes a CAN bus with a CAN-H wire, a CAN-L wire, a pair of CAN bus terminators located at opposite ends of the CAN bus, each terminator having a corresponding known terminator resistance value, a plurality of nodes including controllers wherein at least one of said controllers is a monitoring controller. The monitoring controller includes a detection control routine for detecting the presence of a wire-open fault on the CAN bus, including determining a CAN bus resistance, and determining a wire-open fault on the CAN bus based upon the determined CAN bus resistance and the terminator resistance values.

Abstract: A controller area network (CAN) includes a CAN bus having a CAN-H wire, a CAN-L wire, and a pair of CAN bus terminators located at opposite ends of the CAN bus. The CAN further includes a plurality of nodes including controllers wherein at least one of the controllers is a monitoring controller. The monitoring controller includes a detection control routine for isolating faults on the CAN bus including measuring a CAN-H wire voltage, measuring a CAN-L wire voltage, and isolating a short fault based upon the CAN-H wire voltage and the CAN-L wire voltage.

Abstract: A controller area network (CAN) includes a CAN bus having a CAN-H wire, a CAN-L wire, and a pair of CAN bus terminators located at opposite ends of the CAN bus. The CAN further includes a plurality of nodes including controllers wherein at least one of the controllers is a monitoring controller. The monitoring controller includes a CAN monitoring routine for detecting a wire short fault in the CAN bus and its location.

Abstract: A controller area network (CAN) has a plurality of CAN elements including a communication bus and controllers. A method for monitoring the controller area network CAN includes identifying active and inactive controllers based upon signal communications on the communication bus and identifying a candidate fault associated with one of the CAN elements based upon the identified inactive controllers.

Abstract: A method of diagnosing a fault in an in-vehicle communication system. The in-vehicle communication system includes a transmitting node, at least one receiving node, and a network communication bus coupling the transmitting node to the at least one receiving node. A message is transmitted from the transmitting node to the at least one receiving node over the communication bus. A fault detection technique is applied within the transmitting node for detecting a fault within the transmitting node. A fault detection technique is applied to the at least one receiving node for detecting a fault within the at least one receiving node. A fault detection technique is applied within the network communication bus for detecting a fault within the communication bus. An analyzer collectively analyzes results from each respective detection technique for isolating a fault within the in-vehicle communication system.