Automobile System Diagnosis

As technology advances, more and more electrical and computerized gadgetry is added to cars. A service manual that applies specifically to the vehicle being serviced is a must. Such a manual will provide you with accurate information on the following: location of engine and emission control parts; system wiring and block diagrams; description of the various subsystems for fuel, spark, and emission control; safety precautions and recommended service procedures; specifications for sensors and actuators; accessing of self-diagnosis codes; interpretation of diagnostic trouble codes; tools and instruments necessary for diagnosis and repair.
Special automotive diagnostic scanners are available for accessing information from computerized vehicles through connections to this serial data link. Automotive diagnostic scanners can retrieve fault codes, coolant temperature, vacuum, manifold absolute pressure, and oxygen sensor output. Besides, this information can be displayed on the scanner’s screen, shown as a digital readout, or printed on a piece of paper and used for troubleshooting the system.
Moreover, diagnostic tools can be connected to provide an easy way to access all electrical circuit connections to the engine computer. When used with a digital multimeter, resistance and voltage measurements are easily accessible from all circuits of the computer through the diagnostic tools. The data from the tests are compared with available diagnostic and voltage charts to indicate the problem.
Actually, these are the same tests you would be performing without a diagnostic tool, only now the tests are easy to do. However, it doesn’t mean that you have to use diagnostic tool every time when your car has problems. Sometimes, a visual inspection should always be the first step in troubleshooting any system. A seemingly unrelated mechanical problem such as a cracked or disconnected vacuum hose can have a direct impact on the performance of the system. Similarly, at times, some problems may occur in the system even when there has been no check engine or trouble code signal. What you should remember is that most trouble code are related mainly to inputs, few outputs are monitored. Even if the input does not deviate from the normal reading long enough to be recognized as a problem, this does not completely eliminate it as a source of the problem.
If you are a vehicle enthusiast, you can always buy vehicle diagnostic tools from our website, and then diagnose auto malfunctions by yourself. These vehicle diagnostic tools are：Autel MaxiDAS® DS708，Autel MaxiDiag Elite MD802，Autel MaxiSys MS 908，and so on.