JAC J2 User Manual

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Maintenance Manual for J2 Sedan
Electronic Control System
of Engine
206
Section IV Trouble Diagnosis Procedures for Engine Control System
I.
Diagnosis
with
DTC
1. Instruction
1)
The following Repair
can
be carried
out only
after the
current stable
trouble has
been identified,
otherwise the diagnosis will be wrong.
2)
The "multi-meter"
hereinafter refers to the
digital multi-meter and it
is not
permitted to
use the
analog multi-meter to check the electric control system circuits.
3) When carrying out the Repair for the vehicle
with the
anti-theft system, if the requirement of
replacing the ECM is included in the "Next Steps" column, it is necessary to program the ECM
after replacement.
4)
If the DTC
points to low
voltage of a
specific circuit, it indicates
that the
circuit is likely
to have
short circuit with ground or open circuit; if the DTC points to high voltage of a specific circuit, it
indicates that the circuit is likely to have short circuit with power circuit; if the DTC points to a
circuit trouble, it indicates that the circuit is likely to have broken circuit or a variety of line
troubles.
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2.
Diagnosis
Help
1) If the DTC can not be erased, it means
the trouble is
stable; in case of
the sporadic trouble, it
is
necessary to check whether the connector of wire harness is loosened.
2) The c
heck has
been accomplished with steps above and nothing unusual has
been found.
3)
Effects of
the maintenance
of vehicle, cylinder pressure and
mechanical ignition
timing etc.
on the
system should not be neglected during the inspection and repairing.
4)
Replace
the ECM
to
carry out
the test.
■ If the DTC can
be cleared
at this time,
it means
the trouble site
is at ECM; if the DTC still can
not
be erased at this point, then remount the original ECM and repeat the procedures again to carry out
the Repair.

JAC J2 Specifications

General

Brand	JAC
Model	J2
Category	Automobile
Language	English