FUEL TANK PRESSURE SENSOR RATIONALITY TESTING USING V2X TECHNOLOGY

• US 20170342931A1
• Filed: 05/31/2016
• Published: 11/30/2017
• Est. Priority Date: 05/31/2016
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Dudar, Aed M., Tseng, Fling
• Granted Patent: US 9,926,875 B2
• Time in Patent Office: Days
• CPC Class Codes: B60K 15/03 Fuel tanks chassis frame comprising fluid storage compartment B62D21/16 ; Details of the fuel feeding system related to the fuel tank F02M37/0076
• CPC Class Codes: B60K 2015/0319 with electronic systems, e.g. for controlling fuelling or venting for LPG tanks B60K2015/03013
• CPC Class Codes: B60K 2015/03197 Systems for exchanging data
• CPC Class Codes: B60K 2015/0321 characterised by special sensors, the mounting thereof
• CPC Class Codes: F02D 2041/223 Diagnosis of fuel pressure sensors
• CPC Class Codes: F02D 41/021 Introducing corrections for particular conditions exterior to the engine conjoint control of vehicle sub-units for propelling the vehicle B60W30/18
• CPC Class Codes: F02D 41/222 relating to the failure of sensors or parameter detection devices
• CPC Class Codes: G07C 5/008 communicating information to a remotely located station transmission systems for measured values G08C

Abstract

Methods and systems are provided for conducting a fuel tank pressure transducer rationality test diagnostic procedure in vehicles with sealed fuel tanks. In one example, vehicle-to-vehicle (V2V) or vehicle-to-infrastructure-to-vehicle (V2I2V) technology may be utilized to obtain fuel tank pressure transducer data from a select crowd of vehicles, where the select crowd may be based on the vehicles in the select crowd experiencing similar ambient temperature and weather as the vehicle being diagnosed. In this way, FTPT data from vehicles in the select crowd may be compared to FTPT data in the vehicle being diagnosed, in order to indicate whether the FTPT in the vehicle being diagnosed is functioning as desired, where such a diagnostic can be performed without unsealing the fuel tank on either the vehicle being diagnosed or the vehicles in the select crowd, and which may thus reduce undesired evaporative emissions.

Claims

1. A method comprising:

indicating fuel tank pressure changes from a fuel tank pressure transducer (FTPT) coupled to a fuel tank of a vehicle being diagnosed;

receiving fuel tank pressure indications from a select crowd of vehicles; and

conducting a rationality test of the FTPT by correlating the indicated fuel tank pressure changes from the vehicle being diagnosed with indicated fuel tank pressure changes from the select crowd of vehicles to diagnose functioning of the FTPT.

2. The method of claim 1, wherein conducting the FTPT rationality test on the vehicle being diagnosed commences responsive to one of at least a key-off condition in the vehicle being diagnosed greater than a predetermined threshold duration, or a fuel tank pressure change in the vehicle being diagnosed greater than a predetermined fuel tank pressure change threshold.

3. The method of claim 1, wherein fuel tank pressure change in the vehicle being diagnosed is indicated by the FTPT in the vehicle being diagnosed;

and wherein

fuel tank pressure changes in the select crowd of vehicles is indicated by an FTPT in each of the vehicles comprising the select crowd of vehicles.

4. The method of claim 1, wherein both the fuel tank in the vehicle being diagnosed and fuel tanks in the vehicles comprising the select crowd of vehicles comprise fuel tanks that are sealed except for during refueling events.

5. The method of claim 1, further comprising:

capturing and storing fuel tank vapors in a fuel vapor canister which is selectively coupled to the fuel tank of the vehicle being diagnosed via a fuel tank isolation valve; and

wherein

conducting the FTPT rationality test on the vehicle being diagnosed occurs without coupling the fuel tank in the vehicle being diagnosed to the fuel vapor canister.

6. The method of claim 1, wherein the select crowd is determined based on a first filtering process and a second filtering process;

where the first filtering process selects vehicles within a predetermined distance of the vehicle being diagnosed; and

wherein

the second filtering process selects vehicles from the first filtering process based on one or more conditions related to fuel tank pressure.

7. The method of claim 6, wherein conditions related to fuel tank pressure further include one or more of at least:

presence of a sealed fuel tank, an indicated fuel level within a threshold of a fuel level in the vehicle being diagnosed, a key-off condition, a time since key-off greater than a threshold key-off duration, and/or a fuel tank temperature within a threshold of a fuel tank temperature in the vehicle being diagnosed.

8. The method of claim 1, wherein conducting the FTPT rationality test includes wireless communication between the vehicle being diagnosed and the select crowd of vehicles.

9. The method of claim 8, wherein wireless communication between the vehicle being diagnosed and the select crowd of vehicles involves direct communication, without an intermediate step.

10. The method of claim 8, wherein the vehicle being diagnosed sends a request for indicated fuel tank pressure changes comprising a predetermined time period from each of the vehicles comprising the select crowd;

wherein the vehicle being diagnosed receives the indicated fuel tank pressure changes wirelessly from each of the vehicles comprising the select crowd;

wherein a controller of the vehicle being diagnosed generates an FTPT-based pressure change trend based on the combined data from each of the vehicles that comprise the select crowd; and

wherein

the generated FTPT-based pressure change trend is further compared to indicated fuel tank pressure changes in the vehicle being diagnosed in order to determine whether the FTPT in the vehicle being diagnosed is functioning as desired.

11. A method comprising:

indicating fuel tank pressure changes from a fuel tank pressure transducer (FTPT) coupled to a fuel tank of a vehicle being diagnosed;

during a key-off condition of the vehicle being diagnosed, sending a wireless request to a select crowd of vehicles within a predetermined distance of the vehicle being diagnosed, the wireless request including information pertaining to fuel tank pressure changes in each of the vehicles comprising the select crowd over a predetermined time duration;

receiving wireless responses from the select crowd of vehicles; and

indicating whether the FTPT in the vehicle being diagnosed is functioning as desired based on the responses received from the select crowd and the fuel pressure changes from the FTPT.

12. The method of claim 11, wherein an FTPT-based pressure change trend is generated from the information received from each of the vehicles comprising the select crowd;

and wherein

the FTPT-based pressure change trend includes an average pressure change magnitude and direction.

13. The method of claim 12, further comprising:

determining whether the generated FTPT-based pressure change trend is greater than, or less than, a predetermined threshold pressure change; and

responsive to the generated FTPT-based pressure change trend being less than the predetermined threshold pressure change;

indicating an inconclusive diagnostic responsive to an indicated pressure change in the vehicle being diagnosed correlating with the FTPT-based pressure change trend; and

indicating a fault responsive to the indicated pressure change in the vehicle being diagnosed not correlating with the FTPT-based pressure change trend.

14. The method of claim 13, further comprising:

responsive to the generated FTPT-based pressure change trend being greater than the predetermined threshold change;

indicating the FTPT in the vehicle being diagnosed is functioning as desired responsive to an indicated pressure change in the vehicle being diagnosed correlating with the FTPT-based pressure change trend; and

indicating a fault responsive to the indicated pressure change in the vehicle being diagnosed not correlating with the FTPT-based pressure change trend.

15. The method of claim 11, wherein the select crowd is determined based on a first filtering process and a second filtering process;

where the first filtering process selects vehicles within a predetermined distance of the vehicle being diagnosed;

wherein the second filtering process selects vehicles from the first filtering process based on one or more conditions related to fuel tank pressure;

wherein conditions related to fuel tank pressure further include one or more of at least a presence of a sealed fuel tank, an indicated fuel level within a threshold of a fuel level in the vehicle being diagnosed, a key-off condition, a time since key-off greater than a threshold key-off duration, and/or a fuel tank temperature within a threshold of a fuel tank temperature in the vehicle being diagnosed;

wherein

both the first filtering process and the second filtering process are conducted via wireless communication between the vehicle being diagnosed and a plurality of vehicles in wireless communication with the vehicle being diagnosed.

16. A system for a hybrid vehicle, comprising:

a fuel tank coupled to a fuel vapor canister via a conduit;

a fuel tank temperature sensor positioned in the fuel tank;

a fuel tank isolation valve positioned within the conduit between the fuel tank and the fuel vapor canister and configured to seal the fuel tank from the fuel vapor canister and from atmosphere when closed;

a fuel tank pressure transducer (FTPT) positioned in a vapor recovery line between the fuel tank and the fuel tank isolation valve;

a wireless communication device; and

a controller configured with instructions stored in non-transitory memory, that when executed cause the controller to;

indicate a key-off condition greater than a predetermined key-off duration;

send a wireless request to a plurality of vehicles equipped with wireless communication capabilities within a predetermined distance to the vehicle in order to obtain information pertaining to fuel tank pressure changes in each of the plurality of vehicles;

generate a select crowd of vehicles based on the information pertaining to fuel tank pressure changes; and

compare fuel tank pressure data from the select crowd to fuel tank pressure changes in the hybrid vehicle as indicated by the FTPT in the hybrid vehicle in order to indicate whether the hybrid vehicle FTPT is functioning as desired.

17. The system of claim 16, wherein information pertaining to fuel tank pressure changes in each of the plurality of vehicles includes the presence or absence of a sealed fuel tank, fuel level, whether a key-off condition is indicated, an indicated time since key-off, fuel tank temperature, and ambient temperature/humidity and weather conditions in the vicinity of each of the plurality of vehicles;

and wherein the controller further stores instructions in non-transitory memory, that when executed, cause the controller to;

exclude certain vehicles within the plurality of vehicles from the select crowd responsive to one or more of an absence of a sealed fuel tank, fuel level outside of a threshold fuel level, a key-on condition, a key-off condition for less than a predetermined threshold key-off duration, fuel tank temperature outside of a threshold fuel tank temperature, and ambient temperature/humidity and weather conditions different than that of the hybrid vehicle.

18. The system of claim 17, wherein the threshold fuel level, threshold fuel tank temperature, and threshold key-off duration are based on a fuel level, fuel tank temperature, and a key-off duration in the hybrid vehicle.

19. The system of claim 16, wherein the controller further stores instructions in non-transitory memory, that when executed, cause the controller to:

generate a fuel tank pressure change trend from the fuel tank pressure data acquired from vehicles comprising the select crowd;

where the fuel tank pressure change trend comprises a direction and magnitude of averaged fuel tank pressure change;

and wherein comparing fuel tank pressure data from the select crowd to fuel tank pressure changes in the hybrid vehicle includes determining whether the fuel tank pressure change in the hybrid vehicle correlates with the direction and magnitude of the fuel tank pressure trend.

20. The system of claim 19, wherein the controller further stores instructions in non-transitory memory, that when executed, cause the controller to:

in a first condition, including the fuel tank pressure change trend greater than a threshold;

indicate the hybrid vehicle FTPT is functioning as desired responsive to the fuel tank pressure change in the hybrid vehicle correlating with the fuel tank pressure change trend, and indicate a fault responsive to the fuel tank pressure change in the hybrid vehicle not correlating with the fuel tank pressure change trend; and

in a second condition, including the fuel tank pressure change trend lower than the threshold;

indicate an inconclusive diagnostic test responsive to the hybrid vehicle FTPT correlating with the fuel tank pressure change trend, and indicate a fault responsive to the fuel tank pressure change in the hybrid vehicle not correlating with the fuel tank pressure change trend.