KR20060004114A - Thermostat failure diagnosis controlling method of engine - Google Patents

Abstract

The present invention relates to a thermostat fault diagnosis control method of the engine that can perform the fault diagnosis in the FTP mode more accurately, and can reduce the mishap determination for the regular products, and maintains the thermostat fault diagnosis data (DATA). Separately, the FTP mode is determined as the engine speed (RPM) and the load, and the separate data is set to complete the threshold setting according to the addition of the FTP diagnostic control logic and the vehicle-specific mapping to the thermostat monitoring. (MAPPING) to determine the thermostat failure diagnosis.

Engine, Thermostat, Diagnostics, Control

Description

Thermostat failure diagnosis control method of engine {THERMOSTAT FAILURE DIAGNOSIS CONTROLLING METHOD OF ENGINE}

1 is a flowchart illustrating a thermostat failure diagnosis control method of an engine according to an exemplary embodiment of the present invention.

2 to 4 are diagrams showing experimental data related to thermostat failure diagnosis control of an engine according to an embodiment of the present invention.

The present invention relates to a thermostat failure diagnosis control method of the engine.

In general, the control unit (ECU) has a constant temperature (eg, 77 ° C) after the engine is started to detect when a thermostat mounted in an electronically controlled engine is broken in an open state. ) Is not reached (occurs when driving in cold winter), and when the coolant temperature reaches a certain temperature (eg 77 ° C) and does not reach within a certain time (full open and partial open), a thermostat failure is determined.

It is a function of temperature and average air volume (continuous integration of air volume at start-up) at engine start-up and separates the zones according to the average air volume and starts when the average air volume is converted from one zone to another in the remaining zones except the set prohibited zone. At the time when the remaining time is subtracted from the specified time and the temperature of the average air volume range is changed, a large value is adopted in comparison with the predetermined map (Map, Preset condition) to determine the failure.

By the way, the control logic according to the prior art checks the time when the coolant temperature reaches 77 ° C in the worst case condition to prevent misdiagnosis (diagnosis by failure) of a regular product and sets a margin to check the thermostat failure diagnosis. Doing.

Therefore, in accordance with related laws, thermostat failure diagnosis should be performed in FTP mode (LA-4 mode), which is an authentication test mode, but CARB (California Air Resources Board) cannot be diagnosed in FTP mode with the current DATA setting. Deficiency has been pointed out and from 05MY models, all models should be applied.

However, if the data (DATA) is set to troubleshoot mainly in the FTP mode, there is a problem that it is expected that there will be a lot of cases of judging regular products from the road.

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermostat failure diagnosis control method for an engine that can more accurately perform a failure diagnosis in an FTP mode, and can reduce a false positive determination for a genuine product.

In order to achieve the above object, the present invention, in the thermostat failure diagnosis control method of the engine, while maintaining the thermostat failure diagnosis data (DATA) separately FTP mode as the engine speed (RPM) and the load separately Set the data to complete the threshold setting according to the FTP diagnostic control logic addition, and by performing the vehicle-specific mapping (MAPPING) to thermostat monitoring characterized in that to determine the thermostat failure diagnosis.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. While many specific details, such as the following description and the annexed drawings, are shown to provide a more general understanding of the invention, these specific details are illustrated for the purpose of explanation of the invention and are not meant to limit the invention thereto. And a detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

The embodiment of the present invention determines the FTP mode as the engine speed (RPM) and the load separately while maintaining the thermostat failure diagnosis data DATA, and sets and controls the separate data.

In this regard, FTP diagnostic control logic is added and MAPPING to thermostat monitoring is applied to the vehicle.

That is, an embodiment of the present invention is to complete the threshold setting according to the addition of diagnostic logic in the FTP mode for thermostat monitoring, and applies the FTP in the FTP mode (variable fan) when the existing logic is applied. It adds FTP mode diagnostic logic to prevent vehicle defect caused by the failure of thermostat fault diagnosis.

1 is a flowchart illustrating a thermostat failure diagnosis control method of an engine according to an exemplary embodiment of the present invention.

2 to 4 are experimental data related to the thermostat failure diagnosis control of the engine according to an embodiment of the present invention. FIG. 2 is an average intake air amount condition, FIG. 3 is an FTP mode determination time, and FIG. 4 is an average intake. The cumulative air amount time is shown.

FIG. 2 shows average intake air amount conditions XTHSGAVEL_2B and XTHSGAVEH_2B.

2, the cumulative time at the time of determination is shortened when the air volume region is set to the high air volume region, and when the air volume region is set to the low air region, the discrimination ability for the FTP mode is lost. Set-up to each vehicle type according to the weight and load of each vehicle type) (FTP 2nd Hill standard).

The lower the average intake air amount lower limit (XTHSGAVEL_2B), the greater the risk of reproduction under field conditions.

3 is a diagram showing the FTP mode determination time (XTHSMSTIME_2B).

Referring to FIG. 3, the decision timer selection time is advantageous as soon as possible under the same air volume accumulation condition, but it is necessary to set after the completion diagnosis time of the product so that there is no effect when the thermostat tablet is installed.

When the thermostat is installed, the fault diagnosis time (XBDTHERMO = 78 ℃) is less than 250s (different for each model), so set the selection timer selection time to 270s (set after testing for each model) in consideration of margin.

4 is a view showing the average intake air amount accumulation time (XTTHSM2DLYL_2B, XTTHSM2DLYH_2B).

Referring to FIG. 4, the lower cumulative time limit value (XTTHSM2DLYL_2B) is set to 80 s according to the cumulative intake air amount accumulation time at the selection timer selection time point (XTHSMSTIME_2B = 270s). do.

If the cumulative time upper limit value (XTTHSM2DLYH_2B) is shorter than the time until the end of the determination timer TBWTSWTTHM_M2 Timer, the diagnosis may be stopped. .

A thermostat failure diagnosis control method of an engine according to an exemplary embodiment of the present invention will be described with reference to FIGS. 1 to 4.

The embodiment of the present invention determines the FTP mode as the engine speed (RPM) and the load separately while maintaining the thermostat fault diagnosis data (DATA), and sets the separate data to set the threshold according to the addition of the FTP diagnostic control logic. After completing the configuration, MAPPING for thermostat monitoring is used to determine thermostat failure diagnosis.

First, in step S110 of FIG. 1, the control unit ECU determines whether a thermostat failure diagnosis condition is established.

Here, the thermostat fault diagnosis condition according to an embodiment of the present invention is set to the case where the coolant temperature is within the set range, the difference between the water temperature at start up and the intake temperature at start up is less than the set temperature, the intake air amount is less than the set amount. .

For example, the thermostat fault diagnosis condition is below the cooling water temperature range condition (above 7 ℃ and 77 ℃-the temperature range can be changed according to the regulations and thermostat characteristics), and the difference between the water temperature at start-up and the intake temperature at start-up Set the temperature to be compared to (Example 5 ℃), and the intake air volume is outside the prohibited area (Test example-less than 100 seconds below 5 g / sec, less than 200 seconds above 48 g / sec; depending on the mapping for each model) Set to.

If the thermostat fault diagnosis condition is established in step S110, the controller proceeds to step S112 to determine whether the FTP mode determination water temperature condition is satisfied.

FTP mode judgment The water temperature condition is set when the water temperature is within the setting range at start-up, and the water temperature is set between 20 ℃ ~ 30 ℃ according to the regulations (Test Example-Set when the temperature is over 22 ℃ and below 27 ℃). -Confirmation mapping per vehicle model).

If the control unit satisfies the FTP mode determination water temperature condition, the controller proceeds to step S114 and performs a step of counting the FTP mode determination time.

The FTP mode judgment time is set after the thermostat regular product diagnosis completion time and the time elapsed after a certain time (test example: 270 seconds) after starting the engine.

The FTP mode determination time count is initially counted according to the coolant temperature at startup, and the determination time is initialized according to the amount of FTP diagnostic air (low, medium, high).

Subsequently, the controller proceeds to step S116 to determine whether there is an operation of a component that affects the engine load after the engine is started.

That is, it is determined whether there is no operation of components (for example, air conditioner A / C, power steering P / S, and fan FAN) that affect the engine load after the engine is started.

If the switch information for realizing the operation of the above components is input even once, in step S116, the controller proceeds to step S118 and compares the accumulated time of satisfying the average intake air amount condition.

In other words, it is determined that the determination condition is established that the FTP mode is not.

The average intake air amount condition area according to the embodiment of the present invention is set (Test Examples 23g to 50g).

Then, the average intake air amount accumulation time sets the intake air amount accumulation time lower limit and the upper limit value according to the vehicle type and the transmission (automatic transmission vehicle and manual transmission vehicle).

(Test Example; The lower limit of the average intake air amount accumulated time according to the embodiment of the present invention is set to 80 seconds, the upper limit of the average intake air amount accumulated time is set to 160 seconds.)

If the FTP determination condition is satisfied in step S118 described above, the controller proceeds to step S120 to compare whether the average cumulative air amount is the hollow air amount area.

And, if the average cumulative air amount is the hollow air amount region, the control unit proceeds to (S122) and compares the cooling water temperature with the set temperature.

The set temperature of cooling water is 77 ℃.

Subsequently, if the cooling water temperature is equal to or higher than the set temperature, the control unit proceeds to step S124 and compares the determination time, and when the determination time is 0, determines that the thermostat has failed (S126).

If the determination time in step S124 is not 0, the controller proceeds to step S128 to determine the thermostat state as normal.

On the other hand, if the FTP mode determination water temperature condition is not satisfied in the above (S112), the control unit proceeds to (S130) and performs a step of initializing the determination time count (Count).

The determination time count initialization step initializes the initial count time according to the amount of air (low, medium, high) according to the cooling water temperature at startup.

In operation S132, a step of decreasing the initial count time by the set time for each set time is performed.

For example, it decreases by 1 second every 500 msec from the initial count time.

Next, the judgment subtraction time is readjusted (S134).

Re-adjusting the judgment reduction time may be performed by comparing the time remaining in the small area and the time in the predetermined map at the temperature at which the area is changed when the average cumulative air volume changes from the low area to the middle area. Take time.

When the average cumulative air amount changes from the middle region to the high region, a large time is taken by comparing the time remaining in the small region with the time in the predetermined map at the temperature at which the region changes.

When the control unit proceeds to step S136 and determines whether the current average cumulative air amount is in a low, medium, or high region at the time when the failure diagnosis is made, if the remaining time in the corresponding region is selected, the above-described operation is performed (S122). Proceed to) and compare the coolant temperature with the set temperature.

If the cooling water temperature is greater than or equal to the set temperature in the above-described (S122), the control unit proceeds to (S124) and compares the determination time, and if the determination time is 0 (S126) determines that the thermostat failure (S126).

On the contrary, if the determination time is not 0 in step S124 described above, the controller proceeds to step S128 to determine the thermostat state as normal.

As described above, the thermostat failure diagnosis control method of the engine according to an embodiment of the present invention is a threshold value setting according to the addition of diagnostic logic in the FTP mode for thermostat monitoring and the failure diagnosis during the FTP mode. Confirm the completion and apply it to the memory pinned data ('05MY ROM FIX DATA).

The logic diagnoses the thermostat in the FTP mode by making an FTP mode determination based on the constant driving pattern and the engine load / engine speed range, etc. called the FTP mode.

As described above, the thermostat failure diagnosis control method of the engine according to the present invention can perform the failure diagnosis in the FTP mode, and in accordance with the North American CARB regulations, there is an effect of reducing the fine due to the increase in the deficiency.

In addition, there is an effect that it is possible to prevent the determination of the regular goods to come from the actual road.

Claims (23)

In the thermostat failure diagnosis control method of the engine, While maintaining the thermostat troubleshooting data (DATA), the FTP mode is determined as the engine speed (RPM) and load separately, and the separate data is set to complete the threshold setting according to the addition of the FTP diagnostic control logic and the thermostat. Thermostat failure diagnosis control method of the engine, characterized in that for determining the thermostat failure diagnosis by mapping (MAPPING) to the monitoring (Thermostat Monitoring). The method of claim 1, Determining whether a thermostat failure diagnosis condition is established; Determining whether the FTP mode determination temperature condition is satisfied when the thermostat failure diagnosis condition is established; Counting the FTP mode determination time if the FTP mode determination water temperature condition is satisfied; Determining whether there is an operation of a component that affects the engine load after the engine is started; Comparing a cumulative time for satisfying an average intake air amount condition; Determining the establishment of the FTP mode determination condition; If the FTP determination condition is satisfied, comparing the average accumulated air amount with the hollow air amount area; If the average cumulative air amount is a hollow air amount region, comparing the cooling water temperature with a set temperature; Comparing the determination time when the cooling water temperature is equal to or higher than the set temperature; If the determination time is 0, the thermostat failure diagnostic control method of the engine comprising the step of determining that the thermostat failure. The method of claim 2, The thermostat fault diagnosis condition is that the cooling water temperature is within the set range, the difference between the water temperature at start-up and the intake temperature at start-up is less than the set temperature, and the intake air amount is less than the set amount. Diagnostic control method. The method of claim 3, Thermostat failure diagnosis control method of the engine, characterized in that for determining whether to restart by the difference between the water temperature at start-up and the intake air temperature at start-up to determine the increase in the cooling water temperature by restart. The method of claim 3, Thermostat failure diagnosis control of the engine, characterized in that forbidden zone (intake air amount less than 100 seconds below 5g / sec, less than 200 seconds above 48g / sec) to prevent false detection by excessive and sudden intake air volume Way. The method of claim 2, FTP mode determination water temperature condition is a thermostat fault diagnostic control method for the engine, characterized in that the water temperature is set within the set range at startup. The method of claim 6, FTP mode determination water temperature condition is a thermostat failure diagnostic control method for the engine, characterized in that the water temperature is set to 22 ℃ or more when the temperature is lower than 27 ℃. The method of claim 2, FTP mode determination time is the thermostat fault diagnosis control method of the engine, characterized in that the set after the completion time of thermostat regular product diagnostics. The method of claim 8, FTP mode determination time is the thermostat failure diagnostic control method for the engine, characterized in that the predetermined time has elapsed after starting the engine. The method of claim 2, FTP mode determination time count (Count) is the initial count (Count) according to the coolant temperature at start-up, the thermostat failure diagnosis control of the engine, characterized in that to initialize the determination time according to the FTP diagnostic air volume (low, medium, high) Way. The method of claim 2, An average intake air amount condition is set within a predetermined air amount region thermostat failure control method of the engine. The method of claim 2, The average intake air amount accumulation time is set to the lower limit and the upper limit of the intake air amount accumulation time of the automatic transmission vehicle and the manual transmission vehicle thermostat failure control method of the engine. The method of claim 12, A method for diagnosing thermostat failure diagnosis of an engine, wherein the lower limit value of the accumulated intake air amount is 80 seconds. The method of claim 13, The upper limit of the cumulative average amount of intake air amount is 160 seconds, the thermostat failure diagnosis control method for the engine. The method of claim 2, The thermostat failure diagnosis control method of the engine, characterized in that the coolant temperature set temperature is 77 ℃. The method of claim 2, If the determination time is not 0, the thermostat fault diagnosis control method of the engine, characterized in that the determination is normal. The method of claim 2, Initializing a determination time count if the FTP mode determination water temperature condition is not satisfied; Decreasing the initial count time by the set time for each set time; Readjusting the judgment subtraction time; Comparing the cooling water temperature with the set temperature if the remaining time in the corresponding area is selected after determining the current average cumulative air amount in the low, middle, and high areas at the time of the failure diagnosis determination is made; Comparing the determination time when the cooling water temperature is equal to or higher than the set temperature; If the determination time is 0, the thermostat failure diagnostic control method of the engine, characterized in that it is determined that the thermostat failure. The method of claim 17, The determination time count initialization step includes initializing the initial count time according to the amount of air (low, medium, and high) according to the coolant temperature at start-up. The method of claim 17, A method for diagnosing thermostat failure diagnosis of an engine, characterized in that the engine is reduced by 1 second every 500 msec from an initial count time. The method of claim 17, Re-adjusting the judgment reduction time may be performed by comparing the time remaining in the small area and the time in the predetermined map at the temperature at which the area is changed when the average cumulative air volume changes from the low area to the middle area. Thermostat failure diagnosis control method of the engine, characterized in that taking time. The method of claim 17, Re-adjusting the judgment subtraction time is performed by comparing the time remaining in the small area and the time in the predetermined map at the temperature at which the area changes when the average cumulative air volume changes from the middle area to the high area. Thermostat failure diagnosis control method of the engine, characterized in that taking time. The method of claim 17, The thermostat failure diagnosis control method of the engine, characterized in that the coolant temperature set temperature is 77 ℃. The method of claim 17, If the determination time is not 0, the thermostat fault diagnosis control method of the engine, characterized in that the determination is normal.

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