With the development and improvement of the electronic control technology of the engine from time to time, OBD fault diagnosis is more and more familiar to everyone. Take the starter fault light on the car dashboard as an example. On vehicles with electronically controlled engines, this light will always be on for a few seconds each time the ignition is switched on. In a few seconds, the engine electronic control system will quickly complete the self-test, and the indicator light will go out after the self-test is completed.

If the vehicle suddenly lights up during driving, it means that the vehicle's electronic control system has a fault and needs to be repaired in time. This fault usually requires a special diagnostic computer to connect to the OBD diagnostic interface on the vehicle to read the fault. Code and data flow can be used for fault diagnosis and analysis.

What is OBD?

OBD means an on-board diagnostic (OBD) system for emission control. It must have the function of identifying the possible fault area and storing the information in the memory of the electronic control unit in the form of fault code. OBD is a system that uses hardware or software to monitor emission-related functions and components, and reminds the driver of corresponding inspection and maintenance in the form of MIL lamp and DTC fault code. It was originally designed to meet environmental regulations and detect whether the vehicle emissions exceed the standard.

The common functions of OBD are as follows:

1. Detect component and system faults at any time to ensure that the emissions of the vehicle during its service life do not exceed the requirements of OBD regulations

2. When the relevant emission fault is detected, the OBD system can send an alarm through the MIL lamp on the instrument panel.

3. Fault vehicles can be repaired in time to reduce vehicle emissions.

4. The OBD system helps technicians to quickly diagnose, repair and reduce maintenance costs.

To sum up, with the increasingly stringent environmental requirements, the importance of OBD has become increasingly prominent. Its introduction is closely related to the use environment, fuel characteristics, driving habits and vehicle conditions. The deficiency of any link will affect the expansion and application of OBD. At the same time, the following supporting conditions also need to be improved: fuel quality, vehicle maintenance technology, consistency of relevant parts, improvement of driver level, improvement of OBD technology itself and support from all aspects of society.