OBD Auto Doctor 2017

When an O2 sensor failure occurs, a DTC or diagnostic trouble code is recorded in the ECU and a check engine light appears on the vehicle’s dash. The DTC must be retrieved using a scanning tool. There are generic or standard OBDII codes along with enhanced or OEM specific codes. Below is a list of the more common OBDII codes, along with the possible cause or causes of the code
In other words, OBD is the language of the Engine Control Unit (ECU), and it was designed to help fight emissions and engine failures.
These codes are used to describe where an issue is occurring on the vehicle and are defined by SAE. These codes, can either be generic or unique to the vehicle manufacturer.
Saving the planet is great (shout out to you citizen scientists!), but what this also means is we can access other features of the car and collect information from and on those parts. Learning how to work with those protocols also means that you can determine what that Malfuction Indicator Light (MIL) (aka the Check Engine Light) on your dash is referring to when it tells you there’s an engine problem. If you or your mechanic has ever read the DTCs (Diagnostic Trouble Codes) on your vehicle, they are using OBD-II.
The codes identify a particular problem area and are intended to provide the technician with a guide as to where a fault might be occurring within a car. The codes should be used in conjunction with the vehicle's service manual to discover and verification which systems, circuits or components should be tested to fully diagnose the fault.

Caution when Relying Only on OBD car doctor 2016

Parts or components should not be replaced with reference to only a DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.

For example, if a DTC reports a sensor fault, replacement of the sensor is unlikely to resolve the underlying problem. The fault is most likely to be caused by the systems that the sensor is monitoring, but might even be caused by the wiring to the sensor itself.

DTCs is may also be triggered by faults earlier down the line. For example, a dirty MAF sensor might be causing the car to overcompensate in its fuel-trim adjustments. As a result, oxygen sensors are likely to report fuel mixture problems.
Torque Free OBD requires the OBD II dongle ELM327 based to communicate with a car.

So to avoid unpredictable hazards when fixing and scanner vehicls based on it's DTC codes -- make sure you get a reliable OBD2 scanner reader that'll thoroughly scan the vehicle for faults beyond traditional DTC codes.

Unfortunately, the actual protocols themselves are not available publicly (if only they’d open source!), but we’ve attempted to collect and clarify as much as possible.
Get the description and the possible cause of the check engine code by searching for the code for all of the major manufacturers with OBD Code Guide and now with quick access to your search history and save results to for use at a later date.
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