An overview of diagnosis
At present, the vehicle factory and the supplier use the on-line diagnosis and the off-line diagnosis diagnosis method.
Online diagnosis: it can run in a car in the process of continuous monitoring of the various components of the electronic control system, such as abnormal, determine the specific fault according to specific algorithm, and in the form of code stored, and start the corresponding fault module function, make the faulty vehicles can be driven to the repair shop for maintenance, maintenance personnel can use car fault self diagnosis function out of trouble codes, fast locate and repair the fault. Therefore, from the perspective of security and maintenance, automotive electronic control system should be equipped with fault self diagnosis function. Since 1979, the General Motors Corporation took the lead in the automotive electronic control system with fault self diagnosis function, the world's major automobile manufacturers have to follow, in their production of the electric car is equipped with a fault self diagnosis function. Fault self diagnosis function, has become a new car factory and maintenance plant is an indispensable and important means of fault detection.
Offline diagnosis: through the external diagnostic equipment to read the corresponding diagnostic information, to achieve the diagnosis operation. The key to realize off-line diagnosis is how to realize the communication mechanism and diagnostic service between the diagnostic equipment and ECU.
At present, the diagnostic protocol standards are mainly divided into two kinds of systems, ISO (Standards Organization International) and SAE (of Automotive Engineers Society). The United States uses the SAE standard system, most countries outside the United States (including China) using the ISO standard system.
In the field of passenger cars, OEM is from a custom diagnostic protocol, and gradually shifted to the ISO standard. In the field of commercial vehicles, OEM continue to use the SAE diagnosis, the European OEM on this basis to increase the ISO diagnosis.
OBD is a complex self diagnostic system for testing the impact of vehicle emissions on parts and systems of failure.
All OBDII or EOBD equipped cars must have:
Standardized data diagnostic interface
- standardized decoder
- standardized electronic communication protocol.
- standardized diagnostic trouble codes
- standardized service intelligence
OBD2 Scanner means you can read the car fault codes from obd socket.OBD2 Scanner can works on all vehicles from 1996 to now because obd2 was used on cars AFTER 1996.You can use OBD2 Scanner to read car faulty codes and erase them.Some of them has special function such as data stream and so on.
OBDMORE.COM provides kinds of obd2 scanner at different price and functions.You can find a most suitable one for your car.