汽车故障诊断与排除的基本方法 Core tip: the basic method of automobile fault diagnosis and troubleshooting is the basis of troubleshooting and the effective means to improve the efficiency of vehicle maintenance. In order to diagnose faults quickly and accurately, it is necessary to understand the basic thinking and methods of diagnosing faults, and to master the basic requirements and methods for troubleshooting. First, the basic thinking and methods of fault diagnosis, the diversity of vehicle fault phenomena and the complexity of the cause, lead to the diversity and uncertainty of the thinking and methods of fault diagnosis...

The basic method of automobile fault diagnosis and troubleshooting

The correct diagnosis of the fault location is the basis of troubleshooting, but also an effective means to improve the efficiency of vehicle maintenance. In order to diagnose faults quickly and accurately, it is necessary to understand the basic thinking and methods of diagnosing faults, and to master the basic requirements and methods for troubleshooting.

I. Basic Thinking and method of diagnosing faults The complexity and diversity of automobile fault phenomenon reason, caused the diversity of ideas and methods of fault diagnosis and uncertainty, but on the whole, the basic ideas and methods should be based on the first mechanical electronics, first special, easy to difficult, simple to complex primary diagnosis. 1, the basic process of diagnosing faults The basic process of diagnosing automobile faults usually includes the following steps: inquiring the situation, reproducing the fault phenomenon, determining the fault characteristics, analyzing the cause of the trouble, drawing up the inspection scope and finding the fault point.

Ask about the situation. Mainly to the driver to understand the vehicle before the failure of some basic information, such as vehicle mileage, vehicle maintenance and repair, the use of vehicles at ordinary times, before the failure of the special phenomenon.

Reproduce the fault phenomenon. By means of a certain method and technical means, the phenomenon of failure will be manifested, such as in-situ launch, road test, etc.. For continuous reproduction of fault, fault phenomena are generally easier; but some of the intermittent fault, because the fault occurs only in a particular environment, so the need to reproduce by means of fault simulation environment, such as through vibration, heating, water, or load (load) etc..

Determine fault characteristics. The fault phenomenon caused by a fault is usually characterized by its specific fault, that is, fault characteristics, and it is very important to find out the fault characteristics and reduce the diagnostic range and diagnose the fault quickly. For example, a unit of SX2190 commercial vehicles, in the execution of the task, suddenly appeared vehicle underpowered, the engine running weak, until slow flameout. Driving on the phone reflects: hit the starter, no car, using electric fuel pump exhaust, found a large number of bubbles discharged, air discharged after the smooth start, but after a period of mileage, the fault occurred again. To further understand the situation that this car since two level maintenance after traveling around 5000km, which found no such fault, but the recent difficult starting, generally according to the electric fuel pump, and the electric fuel pump and found no leakage phenomenon. The diesel filter was cleaned two days before the failure. From the basic information reflected by the driver above, it can be determined that the car has many fault phenomena, such as difficult starting, engine running, vehicle power shortage and engine flameout,

But what fault can represent fault characteristics? It is clear that the engine itself is the most representative of the breakdown characteristics of the car.

Analyze the cause of the trouble. According to the specific structure and fault characteristics of the car, the cause of the trouble is analyzed. In the example above causes the engine to stall.

A. tank without oil. B, the diesel line is not sealed and enters the air. C. diesel filter and diesel pipe blocked. Core tip: the basic method of automobile fault diagnosis and troubleshooting is the basis of troubleshooting and the