Method for automatically adapting the conditions for establishing a diagnostic by an on-board diagnostic system

• US 10,410,437 B2
• Filed: 10/24/2016
• Issued: 09/10/2019
• Est. Priority Date: 10/26/2015
• Status: Active Grant

• Current Assignee: Vitesco Technologies GmbH (Continental AG)
• Original Assignee: Continental Automotive France (Continental AG)
• Inventors: Boyer, Jean-Luc, Pasian, Frederic
• Primary Examiner(s): Kan, Yuri
• Application Number:
  US15/769,524
• Publication Number:
  US 20180315257A1
• Time in Patent Office: 1,051 Days
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/30 Driving style
• CPC Class Codes: B60W 2555/00 Input parameters relating to exterior conditions, not covered by groups B60W2552/00, B60W2554/00
• CPC Class Codes: B60W 2555/20 Ambient conditions, e.g. wind or rain
• CPC Class Codes: B60W 50/0205 Diagnosing or detecting failures; Failure detection models
• CPC Class Codes: F01N 11/00 Monitoring or diagnostic devices for exhaust-gas treatment apparatus , e.g. for catalytic activity safety, indicating or supervising devices for internal combustion engines F02B77/08; testing of machines G01M13/00
• CPC Class Codes: F01N 2550/00 Monitoring or diagnosing the deterioration of exhaust systems
• CPC Class Codes: F01N 2900/0421 using an increment counter when a predetermined event occurs
• CPC Class Codes: F02D 41/1495 Detection of abnormalities in the air/fuel ratio feedback system
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F02D 41/2403 using essentially up/down counters
• CPC Class Codes: F02D 41/2422 Selective use of one or more tables
• CPC Class Codes: G07C 5/04 using counting means or digital clocks
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

An automatic calibration method capable of adapting the set of conditions for performing hardware diagnostics, in an OBD system, with a view to optimizing the compromise between the number of diagnostics performed, in particular in order to comply with legislation relating to the ratio between the number of diagnostics performed on a component and the number of operating cycles, and the accuracy of the diagnostics.

Claims

1. A method for establishing an on-board hardware diagnosis on board a vehicle, by way of a suitable computer executing the following steps:

i. calculating a ratio corresponding to a ratio between a number of instances of a diagnosis, corresponding to the number of times said diagnosis has been performed, and a number of running cycles of the vehicle, corresponding to a number of times said vehicle has had its engine started and has made at least one journey while fulfilling predetermined conditions of use,

ii. defining a configurable level of accuracy of the on-board hardware diagnosis, corresponding to one or more conditions for performing said diagnosis, said conditions being linked to a state of the vehicle, based on at least one of a coolant temperature or a speed of the vehicle, and said level of accuracy being able to adopt a plurality of values in steps between a minimum level of accuracy and a maximum level of accuracy, said level of accuracy being able to be increased step by step, as far as the maximum level of accuracy, or reduced step by step, as far as the minimum level of accuracy,

iii. upon each new running cycle of the vehicle;

if said ratio is higher than a predetermined threshold plus a first margin, increasing the level of accuracy by one step, unless said level of accuracy is equal to the maximum level of accuracy, and

if said ratio is lower than said predetermined threshold plus a second margin, the second margin being smaller than the first margin, reducing the level of accuracy by one step, unless said level of accuracy is equal to the minimum level of accuracy, and

iv. performing the on-board hardware diagnosis under performance conditions corresponding to the level of accuracy.

2. The method as claimed in claim 1, wherein the conditions for performing the on-board diagnosis comprise a condition pertaining to a minimum value and a maximum value of the coolant temperature, a condition pertaining to a minimum speed to be reached by the vehicle, and a condition pertaining to a steadiness of the speed of the vehicle for a determined duration.

3. The method as claimed in claim 1, wherein the conditions for performing the diagnosis are modified automatically by way of computer, the conditions for performing the diagnosis being modified on the basis of a driving style of a driver of the vehicle and of an environment.

4. The method as claimed in claim 1 comprising, prior to step iii., verifying that the number of instances is greater than a number of instances, or instances of the diagnosis threshold and, if said number of instances is lower than said instances of the diagnosis threshold, awaiting the next performance of said diagnosis, doing so until said number of instances becomes greater than or equal to said instances of the diagnosis threshold.

5. The method as claimed in claim 4, wherein the instances of the diagnosis threshold is equal to 20.

6. An on-board diagnostic system for a motor vehicle, comprising a computer for implementing the method as claimed in claim 1.

7. The method as claimed in claim 2, wherein the conditions for performing the diagnosis are modified automatically by way of a computer, the conditions for performing the diagnosis being modified on the basis of a driving style of a driver of the vehicle and of an environment.

8. The method as claimed in claim 1, wherein the conditions for performing the diagnosis are modified on the basis of a driving style of a driver of a vehicle and an air temperature or a running profile.