Method for limiting engine torque when error occurs in water sensor of fuel filter

Abstract

A method for limiting an engine torque when a failure occurs in a water sensor of a fuel filter includes sensing the failure of the water sensor installed in the fuel filter through a failure diagnosis logic in a diesel hybrid vehicle. A current vehicle driving mode is checked when the failure of the water sensor is sensed. Whether or not a first time period elapses a first delay time after sensing the failure of the water sensor when the current vehicle driving mode is an engine driving mode is determined. The engine torque is limited and reduced when the first time period elapses the first delay time.

Claims

1. A method for limiting an engine torque when a failure occurs in a water sensor of a fuel filter, the method comprising steps: sensing, by an engine control unit (ECU), the failure of the water sensor installed in the fuel filter through a failure diagnosis logic in a diesel hybrid vehicle; checking, by the ECU, a current vehicle driving mode when the failure of the water sensor is sensed; determining, by the ECU, whether a first time period elapses a first delay time after sensing the failure of the water sensor when the current vehicle driving mode is an engine driving mode; and limiting and reducing, by the ECU, the engine torque when the first time period elapses the first delay time.

2. The method of claim 1, further comprising steps of: storing, by the ECU, failure state information of the water sensor when the vehicle driving mode is a hybrid driving mode in an engine off state after sensing the failure of the water sensor; measuring, by the ECU, a second time period when the vehicle driving mode is changed from the hybrid driving mode to the engine driving mode while storing the failure state information; determining, by the ECU, whether the second time period after changing to the engine driving mode elapses a second delay time; and limiting and reducing, by the ECU, the engine torque during driving when the second time period elapses the second delay time.

3. The method of claim 1, wherein a cluster controller receive failure state information from the ECU to operate a warning device and the warning device alerts a driver the failure of the water sensor when the failure of the water sensor is sensed by the ECU.

4. The method of claim 3, wherein the warning device is one or more of display devices that display a warning light in the cluster and warning labels.

5. The method of claim 4, wherein the ECU senses the failure of the water sensor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof illustrated in the accompanying drawings which are given hereinbelow by way of illustration only, and thus are not limitative of the present disclosure.

(2) FIG. 1 is a flowchart illustrating a process of performing a water sensor failure diagnosis and engine torque limit in the related art.

(3) FIG. 2 is a block diagram illustrating a water sensor, an engine control unit (ECU), and a cluster controller.

(4) FIG. 3 is a diagram for describing a driving mode of a diesel hybrid vehicle.

(5) FIG. 4 is a flowchart illustrating a torque limit process according to the present disclosure.

(6) FIG. 5 is a block diagram illustrating a connection state between a water sensor, an ECU, and a cluster controller in the present disclosure.

(7) It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the disclosure. The specific design features of the present disclosure as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.

(8) In the figures, reference numbers refer to the same or equivalent parts of the present disclosure throughout the several figures of the drawing.

DETAILED DESCRIPTION

(9) Hereinafter reference will now be made in detail to various embodiments of the present inventive concept, examples of which are illustrated in the accompanying drawings and described below. While the disclosure will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the disclosure to those exemplary embodiments. On the contrary, the invention is intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents, and other embodiments, which may be included within the spirit and scope of the disclosure as defined by the appended claims.

(10) Hereinafter, exemplary embodiments of the present inventive concept will be described in detail with reference to the accompanying drawings, so as to be easily implemented by those skilled in the art.

(11) The present disclosure relates to a method for limiting a torque which gives a time enough for a driver to recognize a failure situation before entering torque limitation when a failure is sensed in a water sensor in a diesel hybrid vehicle to dissolve driver's anxiety due to a sudden torque limitation and contribute to improvement of drivability and merchantability of the vehicle.

(12) FIG. 4 is a flowchart illustrating a torque limit process according to the present disclosure, and FIG. 5 is a block diagram illustrating a connection state between a water sensor 10, an ECU 20, and a cluster controller 30 in the present disclosure.

(13) First, when a failure occurs in the water sensor 10 installed in the fuel filter (S11), the ECU 20 receives a signal transmitted from the water sensor 10 to recognize the failure of the water sensor 10 through a failure diagnosis logic (S12).

(14) Next, the ECU 20, which recognizes the failure of the water sensor 10, transmits failure state information of the water sensor 10 to the cluster controller 30 through CAN communication and the cluster controller 30 receiving the failure state information operates a warning device in a cluster (S13).

(15) That is, a warning light 31 is on, and simultaneously, warning labels are displayed through a display device 32 to inform a driver a failure condition.

(16) Next, the ECU 20 checks a vehicle driving mode when the failure of the water sensor 10 is sensed (S14). When the current vehicle driving mode is an engine driving mode (engine driving), the ECU 20 performs the torque limit to reduce an engine torque when a first time period after sensing the failure elapses a first predetermined delay time 1 (S15) and informs the driver for repair therethrough.

(17) Accordingly, as compared with the related art in which the engine torque is limited immediately in the failure sensing, the torque limit is performed with a predetermined delay time after sensing the failure. As a result, a time capable of sufficiently recognizing a failure condition by a warning light and warning labels may be provided to the driver, thus improving drivability/productivity.

(18) During the failure sensing of the water sensor, while the driving mode is a hybrid driving mode, the failure state of the water sensor 10 is stored in the ECU (S16), and the ECU 20 stores failure state information with respect to the failure of the water sensor 10 which occurs for the hybrid driving mode before entering a next engine driving mode.

(19) Thereafter, when the driving mode of the vehicle is changed to an engine driving mode by a hybrid control unit (HCU) (not illustrated) which is an upper controller, the ECU 20 checks a driving mode change state (S17) to measure a time period from an entry timing into the engine driving mode.

(20) The ECU 20 performs the torque limit that reduces the engine torque when the time elapses a second predetermined delay time 2 (S18), and informs the driver a need for repair therethrough.

(21) In the present disclosure, the first delay time 1 and the second delay time 2 may be the same time value or may be different time values.

(22) As described above, in the present disclosure, unlike the related art in which the engine torque limit is performed immediately when a hybrid driving mode is changed to an engine driving mode when the failure of the water sensor is sensed for the hybrid driving mode, the engine torque limit is performed after a predetermined delay time from a mode change timing, thereby granting a sufficient time required for enabling a driver to recognize a failure condition through a warning light and warning labels and solving anxiety for a vehicle system which is felt by the driver due to immediately torque limit after the mode changing.

(23) Accordingly, in the present disclosure, a time required for enabling a driver to recognize a failure condition may be additionally provided by delaying torque limit entry for a predetermined delay time during failure sensing of the water sensor.

(24) Further, it is possible to solve driver's anxiety due to rapid torque limit and complaints against a vehicle system and contribute to improvement of drivability and productivity of the vehicle.

(25) The inventive concept has been described in detail with reference to exemplary embodiments thereof. However, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.