This study aims to enhance the efficiency of the after-sales service (A/S) process for commercial trucks by implementing a data-driven approach. Traditional A/S methods result in long repair wait times, especially for intermittent faults requiring symptom reproduction. To address this, a system that records Diagnostic Trouble Code (DTC) and Vehicle Running Mode (VRM) data at failure moments is proposed. By storing data from 10 seconds before and after an event, fault diagnosis can be performed without symptom reproduction. Additionally, for exported vehicles, stored data enables remote analysis, overcoming real-time data limitations due to varying environmental factors. This approach improves maintenance reliability, optimizes repair accuracy, and supports proactive quality improvements for newly developed vehicles.

Traffic accidents that occur while driving a car are inevitable, and the characteristics of the body repair field are that each vehicle accident has the same damage and no same repair conditions. Therefore, it is difficult to acquire know-how in vehicle body repair simply by theoretical method of textbook, and the repair method must be changed as new materials and new technologies are applied to it. In particular, roof panels are not frequently damaged by traffic accidents, but they are damaged by falling objects from the roof of a building or the opposite lane, resulting in roof bending and vehicle repair using dent repair to minimize VOC and reduce costs. In this study, the optimal maintenance method is proposed by analyzing the time, cost, and waste generation according to the work method when the degree of damage is large and replacement is required

Considering the features of body repair for automotive body where same damage and repair conditions does not exist in car accident, it is essential to acquire know-how and continuously approach new materials and new technologies on the site of maintenance where the theoretical instruction of textbook cannot react accurately minute by minute. Especially, in case of car repair from unexpected accidents such as body repair or dent repair, it is difficult to satisfy vehicle owners despite their request. Accordingly, this study researched the better maintenance technology to restore to its original state with more improved technology as vehicle owners wish. This study made time to repair reduced by 98% and the cost reduced by 79.6% through the accurate diagnostic technique before repair and maintenance technologies of body crash analysis applying property of high-speed tensile. It also obtains intangible effects including prevention of environmental pollution and maximization of vehicle owners satisfaction.

Considering the features of body repair for automotive body where same damage and repair conditions does not exist in car accident, it is essential to acquire know-how and continuously approach new materials and new technologies on the site of maintenance where the theoretical instruction of textbook cannot react accurately minute by minute. Especially, in case of car repair from unexpected accidents such as body repair or dent repair, it is difficult to satisfy vehicle owners despite their request. Accordingly, this study researched the better maintenance technology to restore to its original state with more improved technology as vehicle owners wish. This study made time to repair reduced by 98% and the cost reduced by 79.6% through the accurate diagnostic technique before repair and maintenance technologies of body crash analysis applying property of high-speed tensile. It also obtains intangible effects including prevention of environmental pollution and maximization of vehicle owners satisfaction.

Considering the features of body repair for automotive body where same damage and repair conditions does not exist in car accident, it is essential to acquire know-how and continuously approach new materials and new technologies on the site of maintenance where the theoretical instruction of textbook cannot react accurately minute by minute. Especially, in case of car repair from unexpected accidents such as body repair or dent repair, it is difficult to satisfy vehicle owners despite their request. Accordingly, this study researched the better maintenance technology to restore to its original state with more improved technology as vehicle owners wish. This study made time to repair reduced by 98% and the cost reduced by 79.6% through the accurate diagnostic technique before repair and maintenance technologies of body crash analysis applying property of high-speed tensile. It also obtains intangible effects including prevention of environmental pollution and maximization of vehicle owners satisfaction.

The two experiments were done on stationary car at 800rpm, 1500rpm and running car on oscilloscope and chassis dynamometer at the speeds of 20km/h, 60km/h. In this experiment, the relativity between waveform, exhaust emissions and fuel consumption through two experimental methods were measured in case of cars with failures in MAP sensor, O sensor, spark plugs. The following results are obtained by analyzing the data relativity between two experimental methods, such as stationary and running tests. A simple stationary test under the maintenance of a decrepit gasoline vehicle would be realistic possibility to predict the fuel consumption and the exhaust emission comparable to results of running test with a chassis dynamometer.