Motor vehicle diagnostic and monitoring system

• US 4,277,772 A
• Filed: 06/17/1980
• Issued: 07/07/1981
• Est. Priority Date: 06/17/1980
• Status: Expired due to Term

• Current Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Kastura, John L., Enyart, David O.
• Primary Examiner(s): Waring, Alvin H.
• Application Number:
  US06/160,152
• Time in Patent Office: 385 Days
• Field of Search: 340/27 R, 340/52 R, 340/52 F, 340/177 R, 340/178, 340/181, 307/10 R, 180/271
• US Class Current: 340/459
• CPC Class Codes: B60K 35/00 Instruments specially adapted for vehicles; Arrangement of instruments in or on vehicles
• CPC Class Codes: F02D 41/1495 Detection of abnormalities in the air/fuel ratio feedback system
• CPC Class Codes: G07C 5/0808 Diagnosing performance data testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005

Abstract

A diagnostic and warning system for a motor vehicle monitors the condition of a number of preselected parameters. When the condition of a parameter is representative of a fault condition, the system energizes a malfunction lamp in the vehicle compartment during the period of the detected fault and the particular fault detected is stored in a nonvolatile memory. A single counter is employed which functions to filter intermittent malfunctions for each of the monitored parameters and which imposes a minimum time duration for energization of the malfunction lamp.

Claims

1. A diagnostic monitoring system for monitoring predetermined parameters in a motor vehicle comprising, in combination:

fault indicating means, the fault indicating means having a first state indicating a fault-free condition and a second state indicating a fault condition;

a temporary storage register for storing fault conditions;

counting means effective to store a count;

means effective to detect fault conditions in the predetermined parameters; and

means effective to (a) store detected fault conditions in the temporary storage register only when said temporary storage register is cleared of all stored fault conditions, (b) clear each terminated fault condition from the temporary storage register at the time said fault condition terminates, (c) recurrently increment the count in the counting means during the period that a malfunction is stored in the temporary storage register, (d) set the fault indicating means to the second state to provide an indication of a fault condition when the count in the counting means attains a first predetermined count, and (e) preset the count in the counting means to a second predetermined count that is less than the first predetermined count when the temporary storage register is cleared of all storage malfunctions when the count is intermediate the first and second counts, the difference between the first and second counts establishing a predetermined minimum time period required for a fault condition to exist before the fault indicating means is set to the second state to indicate a fault condition.

2. A diagnostic monitoring system for monitoring predetermined parameters in a motor vehicle comprising, in combination:

a nonvolatile memory nonvolatile as to motor vehicle operation;

a temporary storage register for storing fault conditions;

counting means effective to store a count;

means effective to detect fault conditions in the predetermined parameters; and

means effective to (a) store detected fault conditions in the temporary storage register only when said temporary storage register is cleared of all stored fault conditions, (b) clear each terminated fault condition from the temporary storage register at the time said fault condition terminates, (c) recurrently increment the count in the counting means during the period that a fault condition is stored in the temporary storage register, (d) store the fault conditions stored in the temporary storage register in the nonvolatile memory and clear the fault conditions stored in the temporary storage register when the count in the counting means attains a first predetermined count, and (e) preset the count in the counting means to a second predetermined count that is less than the first predetermined count when the count in the counting means attains the first predetermined count or when the temporary storage register is cleared of all stored fault conditions, the difference between the first and second counts establishing a predetermined minimum time period required for all fault conditions to be continuous before being stored in the nonvolatile memory.

3. A diagnostic monitoring system for monitoring predetermined parameters in a motor vehicle comprising, in combination:

a nonvolatile memory nonvolatile as to motor vehicle operation;

fault indicating means, the fault indicating means having a first state indicating a fault-free condition and a second state indicating a faulted condition;

a temporary storage register for storing fault conditions;

counting means effective to store a count;

means effective to detect fault conditions in the predetermined parameters; and

means effective to (a) store detected fault conditions in the temporary storage register only when said temporary storage register is cleared of all stored fault conditions, (b) clear each terminated fault condition from the temporary storage register at the time said fault condition terminates, (c) recurrently increment the count in the counting means during the period that a fault condition is stored in the temporary storage register and recurrently decrement the count in the counting means when the temporary storage register is cleared of all stored fault conditions, (d) set the fault indicating means to the second state to provide an indication of a faulted condition when the count in the counting means attains a first predetermined count that is greater than a second predetermined count, (e) store the fault conditions stored in the temporary storage register in the nonvolatile memory, clear the fault conditions stored in the temporary storage register and preset the count in the counting means to a third count greater than the first count when the count in the counting means attains the first count or a fourth count greater than the third count;

(f) preset the count in the counting means to the second count when the temporary storage register is cleared of all stored malfunctions while the count is intermediate the first and second counts;

(g) preset the count in the counting means to the third count when the temporary storage register is cleared of all stored malfunctions while the count is intermediate the third and fourth counts; and

(h) set the fault indicating means to the first state to indicate a fault-free condition when the count in the counting means is decremented to a predetermined fifth count equal to or less than the second count, the difference between the first and second counts and the third and fourth counts being equal and establishing a predetermined minimum time period required for fault conditions to be continuous before being stored in the nonvolatile memory and before setting the fault indicating means to its second state to indicate a fault condition and the difference between the third and fifth counts establishing a predetermined minimum time period for the fault indicating means to be in the second state.