Maintenance Manual for J2 Sedan
Electronic Control System
of Engine
173
IV. Engine Trouble Diagnosis
1.
Trouble diagnosis general for engine control system
In case of failure with Engine Electronic control system components (such as sensor, ECM, injector),
fuel may be cut off or insufficient fuel will be supplied resulting in following conditions:
a.
Starting hardship or failure of engine
b.
Unstable idle
c.
Poor drivability
If any of these situations occurs, first of all, carry out the regular inspection including the basic
inspection of engine (ignition system trouble and correct adjustment of engine etc.). Then inspect the
sub-assemblies of the electronic control system with trouble diagnose apparatus.
Attention:
■
Before dismantling or installing any component, read the DTC at first and then disconnect
battery negative poles.
■
Before disconnecting battery cables, firstly turn off the ignition switch. If battery cable is
disconnected with engine rungin or ignition at ON position, ECM may be damaged.
■
The harness between the ECM and sensor should be shielded by the grounding wire connected to
the vehicle body in order to prevent the interference from the ignition system and radio. If fails,
the harness should be replaced.
■
When checking the charging state of engine, don’t disconnect the negative pole of battery to
prevent damage of ECM.
■
When using the outside charger to charge the battery, it is necessary to disconnect battery cable
to prevent damage of ECM.
