METHOD AND DEVICE FOR IDENTIFYING ERRORS IN EMISSION-RELEVANT CONTROL DEVICES IN A VEHICLE

• US 20100305811A1
• Filed: 11/11/2008
• Published: 12/02/2010
• Est. Priority Date: 11/28/2007
• Status: Active Grant

• Current Assignee: Vitesco Technologies GmbH (Continental AG)
• Original Assignee: Continental Automotive GmbH (Continental AG)
• Inventors: Hofmeister, Carl-Eike, Käsbauer, Michael
• Granted Patent: US 9,181,891 B2
• Time in Patent Office: Days
• US Class Current: 701/35
• CPC Class Codes: F02D 2041/224 Diagnosis of the fuel system
• CPC Class Codes: F02D 2041/228 Warning displays
• CPC Class Codes: F02D 2200/0614 Actual fuel mass or fuel injection amount
• 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 41/221 relating to the failure of actuators or electrically driven elements
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method and a device for identifying errors in emission-relevant control devices of a vehicle, such as the injection of fuel into a cylinder, allows error identification even if none of the sub-systems exceeds a predetermined threshold value. The method has the following steps: determining whether at least one parameter, which permits conclusions to be drawn about the emission behaviour of the respective control device, lies in a desired range; if the parameter lies outside said desired range, an error value that correlates to an increase in emissions is stored; if the parameter is in the desired range, an error value of zero is stored; a total error value is formed from all error values of the control device and an error message is output if the total error value exceeds a predetermined threshold value.

Claims

1. A method of detecting faults in a plurality of emission-relevant control devices comprising the steps:

a) determining whether at least one parameter, which allows a conclusion to be drawn about the emission behavior of the respective control device, lies within a setpoint range,

b) if the parameter lies outside of the setpoint range, storing a fault value that correlates with an emission increase,

c) if the parameter lies within the setpoint range, storing a fault value of zero,

d) wherein a total fault value is formed from all of the fault values of the control devices, and

e) wherein a fault message is output if the total fault value exceeds a defined threshold value.

2. The method according to claim 1, wherein in step a) the parameter, if it lies outside of the setpoint range, is first adapted in at least one adaptation cycle and then it is determined whether the parameter after the adaptation again lies outside of the setpoint range.

3. The method according to claim 1, wherein a fault code is stored if in step b) it is determined that the parameter lies outside of the setpoint range, wherein at least one of:

the fault code characterizes the respective control device as faulty and wherein a fault code is stored if in step c) it is determined that the parameter lies within the setpoint range, wherein the fault code characterizes the respective control device as fault-free.

4. The method according to claim 3, wherein, if the total fault value of the control devices reaches or exceeds the threshold value, the fault codes remain stored.

5. The method according to claim 1, wherein the emission-relevant control devices are the cylinders of an engine of a vehicle.

6. The method according to claim 1, wherein as a parameter a fuel quantity that is injected into the respective cylinder is determined.

7. The method according to claim 6, wherein the fuel quantity in the step a) is injected with an injection time, wherein the injection is an injection time for example of a preceding cycle, and then it is determined whether the fuel quantity lies within the setpoint range.

8. The method according to claim 6, wherein in the adaptation cycle the fuel quantity is adapted at least by adjustment of the injection time and then it is determined afresh whether the fuel quantity lies within or outside of the setpoint range.

9. The method according to claim 1, wherein the fault value that correlates with the emission increase is a scalar quantity.

10. The method according to claim 1, wherein the fault value is zero if the fuel quantity lies within the setpoint range and the more the value deviates from the setpoint range the greater it becomes.

11. The method according to claim 1, wherein the total fault value is the sum of the fault values of the individual control devices.

16. The method according to claim 4, wherein the threshold value is an emission limit value.

12. An arrangement for detecting faults in a plurality of emission-relevant control devices comprising:

a) a device for determining whether or not at least one parameter, which allows a conclusion to be drawn about the emission behavior of the respective control device, lies within a setpoint range,

b) a memory device for storing a fault value, which correlates with an emission increase, if the parameter lies outside of the setpoint range and for storing a fault value of zero if the parameter lies within the setpoint range, and

c) a device for determining a total fault value from all of the fault values of the control devices and for outputting a fault message if the total fault value exceeds a predetermined threshold value.

13. The arrangement according to claim 13, wherein an adaptation device is provided, which adapts the parameter if said parameter lies outside of the setpoint range.

14. The arrangement according to claim 13, comprising a memory code device for storing a fault code for the respective control devices, wherein the memory code device stores “

faulty”

as a fault code for a control device if the parameter lies outside of the setpoint range, and wherein the memory code device stores a “

fault-free”

fault code for a control device if the parameter lies within the setpoint range.

15. The arrangement according to claim 13, wherein a warning light in a vehicle flashes if the device for determining the total fault value establishes that the total fault value exceeds the predetermined threshold value.

17. A system for detecting faults in a plurality of emission-relevant control devices comprising:

a) means for determining whether at least one parameter, which allows a conclusion to be drawn about the emission behavior of the respective control device, lies within a setpoint range,

b) storing means for storing a fault value that correlates with an emission increase if the parameter lies outside of the setpoint range,

c) means for storing a fault value of zero if the parameter lies within the setpoint range,

d) means for forming a total fault value from all of the fault values of the control devices, and

e) means for outputting a fault message if the total fault value exceeds a defined threshold value.

18. The system according to claim 17, further comprising means for first adapting the parameter, if it lies outside of the setpoint range, in at least one adaptation cycle and for determining whether the parameter after the adaptation still lies outside of the setpoint range.

19. The system according to claim 17, further comprising means for storing a fault code if it is determined that the parameter lies outside of the setpoint range, wherein at least one of applies:

the fault code characterizes the respective control device as faulty and wherein a fault code is stored if in step c) it is determined that the parameter lies within the setpoint range, wherein the fault code characterizes the respective control device as fault-free.

20. The system according to claim 19, wherein, if the total fault value of the control devices reaches or exceeds the threshold value, the fault codes remain stored.