User's Manual

G-scan2 User Manual
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OBD-II
On Board Diagnostics was designed and mandated in order to monitor malfunction or failure of the
car’s emission control system. By illuminating the warning lamp on the dashboard, the OBD
system alerts the driver in case the emission control system is failing or inefficient, allows the
ordinary mechanic may immediately comprehend what is the problem by use of a proper diagnostic
device, consequently contributes to minimizing the chance of emitting excessive exhaust gas.
OBD-II was introduced as an update of OBD in a way of increasing the efficiency of OBD system
by standardization. Thanks to the efforts made for standardization, a mechanic can get the
fault code information and data from all the cars that support ISO and SAE industrial standards
regardless of brand or car make.
The shortcoming of standardization is the narrowed scope of information: what you can get is the
emission related minimum scope of information based on “commonly found in every car”
concept.
OBD-II Fault Codes
SAE and ISO industrial standard documents define the OBD-II and EOBD codes are consisted of a
three-digit numeric code preceded by an alpha-numeric designator.
The alpha-numeric designators are "P0~P3", "B0~B3", "C0~ C3" and "U0~ U3" corresponding to
Power train, Body, Chassis, Network Communication systems.
Codes system Included sub-systems (examples)
P0*** ~ P3*** Power train Engine, Transmission
C0*** ~ C3*** Chassis ABS, Suspension, Traction
B0*** ~ B3*** Body Airbag, Air conditioning, lighting
U0*** ~ U3*** Network CAN, Inter-system communication
Manufacturer Specific Fault Codes
Not all the fault codes were standardized. The fault codes that can be commonly applied to any
“internal combustion” vehicles were defined as standard codes. This is also called as “Generic
codes” or ‘Core codes
The larger portion of the entire codes was not standardized due to fundamental differences of each
car Make’s system design or diagnostic strategy. The codes that are reserved for each car
manufacturer’s own definition are called “Enhanced Codes” or “Non-standard codes”