MOTOR-VEHICLE ON-BOARD DIAGNOSTICS TO DISTINGUISH DEGRADATION FROM TAMPERING

• US 20130116881A1
• Filed: 11/04/2011
• Published: 05/09/2013
• Est. Priority Date: 11/04/2011
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Bogema, John Paul, Lyon, Peter Mitchell, Zimmerman, Bret Alan, Fagerman, Todd, Crompton, Todd
• Granted Patent: US 9,068,492 B2
• Time in Patent Office: Days
• US Class Current: 701/29.2
• CPC Class Codes: F01N 2550/05 Systems for adding substances into exhaust
• CPC Class Codes: F01N 2550/24 Determining the presence or absence of an exhaust treating device
• CPC Class Codes: F01N 2900/0416 using the state of a sensor, e.g. of an exhaust gas sensor
• CPC Class Codes: F01N 3/035 with catalytic reactors , e.g. catalysed diesel particulate filters
• CPC Class Codes: F01N 3/2066 Selective catalytic reduction [SCR]
• CPC Class Codes: F02D 2041/228 Warning displays
• 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: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method for responding to conditions detected in an on-board diagnostic unit of a motor vehicle and signaling degradation of a component of the motor vehicle. The method includes providing a first response if the conditions signal degradation of the component due to tampering, and providing a second response if the conditions signal degradation of the component not due to tampering.

Claims

1. A method for responding to conditions detected in an on-board diagnostic unit of a motor vehicle and signaling degradation of a component of the motor vehicle, the method comprising:

providing a first response if the conditions signal degradation of the component due to tampering; and

providing a second response if the conditions signal degradation of the component not due to tampering.

2. The method of claim 1 further comprising detecting the conditions within a single drive cycle of the motor vehicle.

3. The method of claim 2 wherein the second response includes determining whether the conditions are again detected in a second drive cycle of the motor vehicle.

4. The method of claim 1 wherein the first response is provided if the conditions are detected within a predefined interval following startup of the motor vehicle.

5. The method of claim 1 wherein the first response is provided if the conditions are detected within a predefined interval following an idle period exceeding a threshold duration.

6. The method of claim 1 wherein the second response is provided if the motor vehicle is moving faster than a threshold speed when the conditions are detected.

7. The method of claim 1 wherein the second response is provided if an exhaust-system of the motor vehicle is above a threshold temperature when the conditions are detected.

8. The method of claim 1 wherein the first response includes setting a first flag in an electronic control system of the motor vehicle, and wherein the second response includes setting a second flag different than the first.

9. The method of claim 1 wherein the first response includes operating the vehicle in an inducement mode to encourage reversal of the tampering.

10. The method of claim 1 wherein the first response imposes a greater restriction on operation of the motor vehicle than does the second response.

11. The method of claim 1 wherein the first response includes preventing the vehicle from exceeding a threshold speed.

12. The method of claim 1 wherein the first response is provided if the conditions persist for a threshold duration, and wherein the second response is provided if the conditions do not persist for the threshold duration.

13. The method of claim 12 wherein the threshold duration is ten minutes or more.

14. The method of claim 1 wherein the component is an emissions-control component.

15. A method comprising:

detecting, in an on-board diagnostic unit of a motor vehicle, conditions signaling degradation of a motor-vehicle component;

providing a first response if the conditions signal degradation of the component due to tampering; and

providing a second response if the conditions signal degradation of the component not due to tampering.

16. The method of claim 15 wherein detecting the conditions include comparing first sensor data to a threshold above which the component degradation is sufficient in degree to be caused by tampering.

17. The method of claim 16 further comprising determining, based on second sensor data, whether the degradation sufficient in degree to be caused by tampering occurred during circumstances consistent with tampering.

18. The method of claim 17 wherein said detecting and said determining yield a boolean result indicating tampering when affirmative, the method further comprising debouncing the boolean result asymmetrically, such that an affirmative result is filtered with a longer time constant, and a negative result is filtered with a shorter time constant.

19. An on-board diagnostic unit for a motor vehicle comprising memory that encodes instructions readable by a processor and causes the processor to:

receive data from a sensor in the vehicle;

compare the data to a threshold above which degradation of a component is sufficient in degree to be caused by tampering;

determine whether the degradation sufficient in degree to be caused by tampering occurred during circumstances consistent with tampering;

provide a first response if the degradation is sufficient in degree to be caused by tampering and occurred during circumstances consistent with tampering; and

provide a second response if the degradation is insufficient in degree to be caused by tampering or occurred during circumstances not consistent with tampering.

20. The unit of claim 19 wherein the instructions cause the processor to receive the data, compare the data, and determine whether the degradation occurred during circumstances consistent with tampering, all in one drive cycle of the motor vehicle.