OBD2 code reader was started to improve the cumbersome obd1 which is hard to use. There was an outcry also from the automotive industry to standardize the getting of the code without buying too many equipments.

What you should know before buying an obd2 code reader

Before 1995 or older vehicles made in North America, the fault code can be diagnosed by using a jumper wire connected in the vehicle’s diagnostic link. When this is done, the engine computer will be commanded to set up the diagnostic mode. This results in the faulty codes being flashed in the vehicle dash panel. The flashing light will be counted and the resulting codes compared to a fault code list available from the vehicle manufacturer.

However, beginning 1996, all vehicles has stopped this practice because of the confusion in counting the flashes. An alternative was used whereby a scanner or code reader is used instead to avoid the counting of the flashes in your dash panel which is awkward. This implementation also help standardized the diagnostic link connector into one location by the left side of the driver’s steering column under the dash.

Most generic code scanner being offered displays the code number of the fault code and could give a brief description of the code depending on the scanner cost. Still the better ones has the ability to erase the code. However, since it only reads the code, it does not monitor the engine computer or the sensors while the engine is operating. In essence, it does not give the solution to the fault code but lead you to the circuit or system looking for the culprit.

Remember: a code scanner does not tell you which defective part to replace but it indicates that the engine computer has recorded a fault and use that information as indicator where to begin the inspection. This should be understood so that we don’t assume that this code reader can find and fix the problem. What actually happens, as soon as you have the code detected, you need a list of common fixes for that particular code so a fix can be started. Furthermore, if the common fixes are not enough, a wiring diagram is also needed so that the wiring circuits and location can be identified.

Finally, it is important that a code reader, common fixes and wiring diagram are effective only when used with an online troubleshooting advisor so you can fix the problem your self. This will help you in diagnosing the trouble code without wasting your time and damaging your engine circuits, computer, wirings including yourself.

Tip when buying a obd2 code reader:

Code reader can display generic or common codes which might not be applicable to all vehicle models. When buying a code reader, make sure to ask for one applicable to your vehicle. Example: Asian or European vehicle code reader will not work on North American vehicles.

Code readers are classified into applications:

Power train code which is what you need to fix engine problems (P0001-P2800)
Body control code which are used to fix body control functions such vehicle accessories (B0001-B4000)
Network code which deals only in computer communication (U0001-U2200)
Chassis code for the vehicle chassis (C0000-C1800)
Manufacture code (DTC 01-199)

Unless you want to be a full pledge mechanic, only concentrate on power train code reader since it will cover most of your engine problem. All the rest will need some specialized training.

For a detailed ONE on ONE online support to fix your OBD2 code, join ATS (LIFETIME membership)

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