1
.
Safety
Precautions
and
Warnings
To
prevent
personal
injury
or
damage
to
vehicles
and
/
or
the
scan
tool
,
read
this
instruction
manual
first
and
observe
the
following
safety
precautions
at
a
minimum
whenever
working
on
a
vehicle
:
Do
not
attempt
to
operate
or
observe
the
tool
while
driving
a
vehicle
.
Operating
or
observing
the
tool
will
cause
driver
distraction
and
could
cause
a
fatal
accident
.
Wear
safety
eye
protection
that
meets
ANSI
standards
.
Operate
the
vehicle
in
a
well
ventilated
work
area
:
Exhaust
gases
are
Poisonous
.
Put
the
transmission
in
PARK
(
for
automatic
transmission
)
or
NEUTRAL
(
for
manual
transmission
)
and
make
sure
the
parking
brake
is
engaged
.
Keep
the
scan
tool
dry
,
clean
,
free
from
oil
/
water
or
grease
.
Use
a
mild
detergent
on
a
clean
cloth
to
clean
the
outside
of
the
scan
tool
,
when
Necessary
.
Always perform automotive testing in a safe environment
The first generation of On-Board Diagnostics (called OBD I) was developed by
the California Air Resources Board (CARB) and implemented in 1988 to monitor
some of the emission control components on vehicles. As technology evolved
and the desire to improve the On-Board Diagnostic system increased, a new
generation of On-Board Diagnostic system was developed. This second
generation of On-Board Diagnostic regulations is called "OBD II".
The OBD II system is designed to monitor emission control systems and key
engine components by performing either continuous or periodic tests of specific
components and vehicle conditions. When a problem is detected, the OBD II
2. General Information
2.1 On-Board Diagnostics (OBD) II
6
EN
system turns on a warning lamp (MIL) on the vehicle instrument panel to alert
the driver typically by the phrase “Check Engine” or “Service Engine Soon”. The
system will also store important information about the detected malfunction so
that a technician can accurately find and fix the problem. Here below follow
three pieces of such valuable Information:
OBD II Diagnostic Trouble Codes are codes that are stored by the on-board
computer diagnostic system in response to a problem found in the vehicle.
These codes identify a particular problem area and are intended to provide you
with a guide as to where a fault might be occurring within a vehicle. OBD II
Diagnostic Trouble Codes consist of a five-digit alphanumeric code. The first
character, a letter, identifies which control system sets the code. The other four
characters, all numbers, provide additional information on where the DTC
originated and the operating conditions that caused it to be set. Below is an
example to illustrate the structure of the digits:
DTC
Example
P
0
5
2
0
Systems
B
=
Body
C
=
Chassis
P
=
Powertrain
U
=
Network
Last
two
digits
identify
individual
component
within
the
system
Code
Type
Generic
(
SAE
):
P0
B0
C0
U0
Manufacturer
Specific
:
P1
,
P2
B1
,
B2
C1
,
C2
U1
,
U2
Sub
-
systems
1
=
Fuel
and
air
metering
2
=
Ignition
system
or
engine
misfire
3
=
Auxiliary
emissions
controls
4
=
Vehicle
speed
control
and
idle
controls
5
=
Computer
output
circuits
6
=
Transmission
controls
Figure
1
-
2
:
Explanation
of
a
diagnostic
trouble
code
.
7
EN
eQP-120 User’s Manual
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eQP-120 User’s Manual
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