Abstract: A diagnostic system for a vehicle electrical system includes a first voltage divider circuit that outputs a second voltage in response to a first voltage, and a second voltage divider circuit that outputs a third voltage in response to the first voltage. An analog-to-digital converter outputs first and second voltage values, respectively, based on the second and third voltages, respectively. A microcontroller determines a first compensated voltage value utilizing the first voltage value and a compensation value. The microcontroller determines a difference value based on the first compensated voltage value and the second voltage value. The microcontroller commands the high side driver circuit and the low side driver circuit to transition the contactor to an open operational position when the difference value is greater than a threshold difference value.

Abstract: A diagnostic having an analog-to-digital converter that is electrically coupled to an output port of a first analog multiplexer and an output port of a second analog multiplexer is provided. The analog-to-digital converter receives the high side voltage level signal and the low side current level signal at first and second times, respectively, and outputs a high side voltage value and a low side current value, respectively, based on the high side voltage level signal and the low side current level signal, respectively, that are received by a microcontroller. The microcontroller commands a high side driver circuit and a low side driver circuit to transition a contact of the contactor to an open operational position when the first analog multiplexer is malfunctioning based on the high side voltage value.

Abstract: A system for controlling operation of first and second electric fans is provided. The system includes a microcontroller that determines when first analog multiplexer is malfunctioning or a first channel of the first analog-to-digital converter is malfunctioning based on first values obtained from the first analog-to-digital converter. The first values are associated with at least one of a first speed signal associated with the first electric fan and a first driving voltage for the first electric fan that are received by the first analog multiplexer. The microcontroller modifies a control signal to induce the second electric fan to operate at a higher rotational speed when the first analog multiplexer is malfunctioning or the first channel of the first analog-to-digital converter is malfunctioning.

Abstract: A diagnostic system for a DC-DC voltage converter having a high voltage switch, a low voltage switch, and a DC-DC voltage converter control circuit is provided. The system includes first and second tri-state buffer ICs and a microcontroller. The first tri-state buffer IC receives a first shutdown indicator voltage from the DC-DC voltage converter control circuit indicating that a first plurality of FET switches in a high side FET IC and a second plurality of FET switches in a low side FET IC have been transitioned to an open operational state. The first tri-state buffer IC outputs a second shutdown indicator voltage to the microcontroller that indicates that the first and second plurality of FET switches have been transitioned to the open operational state.

Abstract: A control system for a DC-DC voltage converter includes a microcontroller having first and second applications. The first application commands the microcontroller to generate a first signal that is received at a first pin on a high side integrated circuit to transition a first plurality of FET switches to an open operational state, and that is received at a first pin on the low side integrated circuit to transition a second plurality of FET switches to the open operational state. The second application commands the microcontroller to generate a second signal that is received at a second pin on the high side integrated circuit to transition the first plurality of FET switches to the open operational state, and that is received at a second pin on the low side integrated circuit to transition the second plurality of FET switches to the open operational state.

Abstract: A diagnostic system for a battery system in accordance with an exemplary embodiment is provided. The battery system includes a battery module electrically coupled to a contactor. The diagnostic system includes a first microcontroller and a second microcontroller operably communicating with the first microcontroller. The second microcontroller is programmed to open the contactor electrically coupled to the battery module if either a first diagnostic indicator flag is equal to a first fault value or a second diagnostic indicator flag is equal to a second fault value. The second microcontroller is further programmed to open the contactor if either a third diagnostic indicator flag is equal to a third fault value or a fourth diagnostic indicator flag is equal to a fourth fault value.

Abstract: A diagnostic system for a DC-DC voltage converter is provided. The diagnostic system includes a first temperature sensor generating a first output voltage indicating a temperature level of a high voltage bi-directional MOSFET switch. The diagnostic system includes a microcontroller that samples the first output voltage at a first sampling rate utilizing a first channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first output voltage is greater than a first threshold voltage. The microcontroller sets a first temperature diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating the high voltage bi-directional MOSFET switch has an over-temperature condition.

Abstract: A control system for controlling operational modes of a DC-DC voltage converter is provided. The DC-DC voltage converter initially has an idle operational mode. The microcontroller having first and second operational mode applications. The first operational mode application determines a first encoded value based on the first operational mode value, and further determines first and second values based on the first encoded value. The second operational mode application determines a second encoded value based on the first operational mode value, and further determines third and fourth values based on the second encoded value. The first operational mode application induces the DC-DC voltage converter to transition to the first operational mode if the second value is equal to the third value.

Abstract: A control system for a DC-DC voltage converter includes a microcontroller having first and second applications. The first application commands the microcontroller to generate a first signal that is received at a first pin on a high side integrated circuit to transition a first plurality of FET switches to an open operational state, and that is received at a first pin on the low side integrated circuit to transition a second plurality of FET switches to the open operational state. The second application commands the microcontroller to generate a second signal that is received at a second pin on the high side integrated circuit to transition the first plurality of FET switches to the open operational state, and that is received at a second pin on the low side integrated circuit to transition the second plurality of FET switches to the open operational state.

Abstract: A control system for controlling operational modes of a DC-DC voltage converter is provided. The DC-DC voltage converter initially has an idle operational mode. The microcontroller having first and second operational mode applications. The first operational mode application determines a first encoded value based on the first operational mode value, and further determines first and second values based on the first encoded value. The second operational mode application determines a second encoded value based on the first operational mode value, and further determines third and fourth values based on the second encoded value. The first operational mode application induces the DC-DC voltage converter to transition to the first operational mode if the second value is equal to the third value.

Abstract: A diagnostic system for a DC-DC voltage converter is provided. A first temperature sensor generates a first temperature signal associated with a buck mode integrated circuit. A first analog multiplexer outputs the first temperature signal to a first analog-to-digital converter which generates a first temperature value. A second temperature sensor generates a second temperature signal associated with a boost mode integrated circuit. A second analog multiplexer outputs the second temperature signal to a second analog-to-digital converter which generates a second temperature value. A microcontroller generates control signals to command first and second bi-directional switches in the DC-DC voltage converter to each transition to an open operational state if the first temperature value is greater than a first threshold temperature value.

Abstract: A system for determining a voltage out-of-range high condition of a battery module is provided. A microcontroller determines first, second, and third voltage values from first, second, and third voltage sensors, respectively, coupled to first, second, and third battery cells, respectively; and determines a battery module voltage value based on a fourth signal. The microcontroller sums the first, second, and third voltage values to obtain a battery module high voltage sum value. The microcontroller generates a first control signal to induce a contactor to transition to an open operational position to electrically decouple the battery module from an electrical load, if a difference between the battery module high voltage sum value and the battery module voltage value is greater than or equal to a battery module voltage out-of-range high error value.

Abstract: A diagnostic system for a battery system having a battery module electrically coupled to a contactor is provided. The battery module has first, second, and third battery cells. The diagnostic system includes a first microcontroller that transitions the contactor to an open operational state if a first battery cell comparator overvoltage flag is equal to a first battery cell analog overvoltage flag value, or a battery module fault line voltage flag is equal to a first battery module fault line voltage flag value.

Abstract: A diagnostic system for a battery system having a battery module electrically coupled to a contactor is provided. The battery module has first, second, and third battery cells. The diagnostic system includes a first microcontroller that transitions the contactor to an open operational state if the first battery cell analog overvoltage flag is equal to the first battery cell analog overvoltage flag value. The first microcontroller further transitions the contactor to the open operational state if the first battery cell comparator overvoltage flag is equal to the first battery cell comparator overvoltage flag value.

Abstract: A diagnostic system for a battery system having a battery module electrically coupled to a contactor is provided. The battery module has first, second, and third battery cells. The diagnostic system includes a first microcontroller that transitions the contactor to an open operational state if a first battery cell analog overvoltage flag is equal to a first battery cell analog overvoltage flag value, or a battery module overvoltage flag is equal to a first battery module overvoltage flag value.

Abstract: A system for controlling operation of first and second electric fans is provided. The system includes a microcontroller that determines when first analog multiplexer is malfunctioning or a first channel of the first analog-to-digital converter is malfunctioning based on first values obtained from the first analog-to-digital converter. The first values are associated with at least one of a first speed signal associated with the first electric fan and a first driving voltage for the first electric fan that are received by the first analog multiplexer. The microcontroller modifies a control signal to induce the second electric fan to operate at a higher rotational speed when the first analog multiplexer is malfunctioning or the first channel of the first analog-to-digital converter is malfunctioning.

Abstract: A diagnostic system for a DC-DC voltage converter is provided. The diagnostic system includes a first temperature sensor generating a first output voltage indicating a temperature level of a high voltage bi-directional MOSFET switch. The diagnostic system includes a microcontroller that samples the first output voltage at a first sampling rate utilizing a first channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first output voltage is greater than a first threshold voltage. The microcontroller sets a first temperature diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating the high voltage bi-directional MOSFET switch has an over-temperature condition.

Abstract: A diagnostic system for a DC-DC voltage converter having a low voltage bi-directional MOSFET switch is provided. The low voltage bi-directional MOSFET switch has first and second nodes. The microcontroller samples a first voltage at the first node at a first sampling rate utilizing a first common channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first voltage is less than a first threshold voltage. The microcontroller sets a first voltage diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating a voltage out of range low fault condition for the analog-to-digital converter.

Abstract: A diagnostic system for a DC-DC voltage converter is provided. The DC-DC voltage converter has a high voltage bi-directional MOSFET switch. The high voltage bi-directional MOSFET switch has a first node and a second node. The microcontroller samples a first voltage at the first node at a first sampling rate utilizing a first common channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first voltage is less than a first threshold voltage. The microcontroller sets a first voltage diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating a voltage out of range low fault condition for the analog-to-digital converter.

Abstract: A system for controlling operation of a contactor is provided. The system stops outputting a control signal to open the contactor, and then measures a low side sense signal from a low side sense circuit electrically coupled to a low side end of a contactor coil, or a high side sense signal from a high side sense circuit that is electrically coupled to a high side end of the contactor coil, to determine whether the contactor has a closed operational position, and if not, the system stops outputting another control signal to open the contactor.