Malfunction detecting method for a vehicle fuel level sensor

• US 6,763,713 B2
• Filed: 12/30/2002
• Issued: 07/20/2004
• Est. Priority Date: 05/29/2002
• Status: Expired due to Fees

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Seo, Je-Young, Kim, Youn-Soo
• Primary Examiner(s): CYGAN, MICHAEL T
• Application Number:
  US10/331,886
• Publication Number:
  US 20030221479A1
• Time in Patent Office: 568 Days
• Field of Search: 732/91, 732/90.R, 731/13, 731/181, 73/55
• US Class Current: 73/291
• CPC Class Codes: F02D 2200/0404 Throttle position
• CPC Class Codes: F02D 2200/602 Pedal position
• CPC Class Codes: F02D 33/003 Controlling the feeding of liquid fuel from storage containers to carburettors or fuel-injection apparatus control of electrical fuel pumps F02D41/3082, controlling fuel flow to a common rail F02D41/3845; Failure or leakage prevention; Diagnosis or detection of failure; Arrangement of sensors in the fuel system; Electric wiring; Electrostatic discharge
• CPC Class Codes: F02D 41/045 Detection of accelerating or decelerating state detection thereof in general G01P
• CPC Class Codes: F02D 41/222 relating to the failure of sensors or parameter detection devices
• CPC Class Codes: F02M 37/0082 Devices inside the fuel tank other than fuel pumps or filters electrical pumps submerged in fuel tanks F02M37/10, jet pumps F02M37/025
• CPC Class Codes: G01F 25/20 of apparatus for measuring liquid level

Abstract

The present invention provides a fuel level sensor malfunction detecting method and system for a vehicle. In the method and system the rate of change in the opening of the throttle valve and the detection of a transmission kick-down are conditions for determining the malfunction of the fuel level sensor, thereby making it possible to detect a malfunctioning fuel level sensor more accurately.

Claims

1. A fuel level sensor malfunction detecting method for a vehicle, comprising:

concluding that monitoring conditions are satisfied;

counting a time period during which (a) the fuel level comes within a target range and (b) a difference between maximum and minimum values of the fuel level is less than a first minimum value;

concluding a change rate of opening of a throttle valve has shown a value greater than a target value during the counted time period;

accumulating malfunction occurrences if the change rate of the throttle valve opening was greater than the target value; and

concluding that the fuel level sensor has malfunctioned if the accumulated malfunction occurrences are greater than a maximum malfunction value.

2. The method of claim 1, wherein the monitoring conditions are satisfied if a battery voltage is above a threshold voltage and if a minimum time period has elapsed after release of a starting mode.

3. The method of claim 2, wherein the counted time period is 200 seconds.

4. The method of claim 1, further comprising:

counting a second time period during which (a) the fuel level is outside the target range and (b) the difference between the maximum and minimum values of the fuel level is less than a second minimum value; and

concluding that the fuel level sensor has malfunctioned if the second time period has elapsed.

5. The method of claim 1, wherein said accumulating comprises accumulating the number of malfunction occurrences if both the change rate of the throttle valve opening was greater than the target value and a kick-down has been detected.

6. A fuel level sensor malfunction detecting method for a vehicle, comprising:

concluding that monitoring conditions are satisfied;

counting a time period during which (a) the fuel level comes within a target range and (b) a difference between maximum and minimum values of the fuel level is less than a minimum value;

concluding a change rate of a throttle valve opening was greater than a target value, or detecting a kick-down during the counted time period;

accumulating malfunction occurrences if the change rate of the throttle valve opening was greater than the target value and the kick-down was detected; and

concluding that the fuel level sensor is malfunctioning if the accumulated malfunction occurrences are greater than a maximum malfunction value.

7. The method of claim 6, wherein the monitoring conditions are satisfied if a battery voltage is above a threshold voltage and if a maximum time period has elapsed after release of a starting mode.

8. The method of claim 6, wherein the counted time period is 200 seconds.

9. The method of claim 6, further comprising:

counting a second time period during which (a) the fuel level is outside the target range and (b) the difference between the maximum and minimum values of the fuel level is less than a second minimum value; and

concluding that the fuel level sensor is malfunctioning if the second time period has elapsed.

10. A method for detecting a failed fuel level sensor in a vehicle, comprising:

determining whether a fuel level sensor output is within a target range;

determining that a difference between a maximum and a minimum fuel level sensor output is below a minimum value;

monitoring the fuel level sensor and a throttle valve opening sensor for a time period wherein the vehicle is moving;

accumulating a malfunction if, during the time period, the throttle valve opening sensor registered a rate of change greater than a target rate; and

concluding that the fuel level sensor is malfunctioning if the accumulated malfunctions exceed a maximum malfunction value.

11. The method of claim 10 wherein said accumulating comprises accumulating a malfunction if, during the time period, both the throttle valve opening sensor registered a rate of change greater than a target rate, and a kick-down was detected.

12. A system for detecting the malfunction of a fuel level sensor, comprising:

a fuel level sensor generating a signal representative of fuel level;

a throttle position sensor generating a signal representative of throttle position;

a battery voltage sensor generating a signal representative of battery voltage;

a vehicle speed sensor generating a signal representative of vehicle speed; and

an electronic control receiving said signals and unit programmed with instructions for determining if the fuel level sensor is malfunctioning based on said signals.

13. The system of claim 12, further comprising a transmission signal input and wherein said instructions further comprise determining if the fuel level sensor is malfunctioning based additionally on a transmission signal.

14. The system of claim 13, wherein said instructions comprise:

concluding that monitoring conditions are satisfied;

counting a time period during which (a) the fuel level comes within a target range and (b) a difference between maximum and minimum values of the fuel level is less than a first minimum value;

concluding a change rate of opening of a throttle valve has shown a value greater than a target value during the counted time period;

accumulating malfunction occurrences if the change rate of the throttle valve opening was greater than the target value; and

concluding that the fuel level sensor has malfunctioned if the accumulated malfunction occurrences are greater than a maximum malfunction value.