Hanatech Multiscan, Руководство оператора

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USER MANUAL For Multiscan
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II. More practical notes --------------------------
A. Technical meaning of OBD2
1. Standardization
a For the technicians and scan tool engi neers, OBD2 has its technical
meaning as bringi ng the standardized methods of vehicle diagnosis to
the chaotic afterm arket where dozens of car m ake use different
diagnostic adapters and communication protocols of their own.
b The 16-pi n trapezoi d di agnostic adapter and a few of most infl uential
com municati on protocols i ncl udi ng ISO9141-2, KWP2000, and SAE
J1850 VPW and PWM form the standard OBD2 specifications.
c Trouble codes and Data stream variabl es were also standardi zed and
opened to public, so that all the scanners that support aforem entioned
standard comm uni cation protocols through the 16-pin OBD2 adapter can
always get the same readouts.
2. Purpose of OBD and OBD2
a. OBD and OBD2 are the nam es of regulati on that were legislated in USA
for the em ission control .
b. On board diagnosti cs was im plemented to m oni tor malfunction or failure
of the emission related parts and com ponents to m inim ize the possibility
of excessi ve exhaust gas em ission by letting the dri ver know that the car
has a problem and the techni ci an immediatel y percei ve what is the
problem when any trouble is detected in the emission control system .
And OBD2 became effective l ater to increase the effi ciency of OBD by
standardization.