Isuzu 2008MY N Series, Руководство по ремонту

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1A-378 Engine Control System (4HK1)
Description and Operation
Engine Control Module (ECM) Description
Engine Control Module (ECM) Service Precautions
Important: The symbol ! warns you of an electric shock
hazard. To avoid shock and possible serious injury, DO
NOT touch the terminals. When disconnecting the
harness connectors, always turn OFF the ignition
switch or disconnect the battery cable.
The engine control module (ECM) is designed to
withstand normal current draws associated with vehicle
operation. Avoid overloading any circuit. When testing
for opens and shorts, do not ground or apply voltage to
any of the ECM circuits unless instructed to do so. In
some cases, these circuits should only be tested using
a DMM. The ECM should remain connected to the
ECM harness.
The ECM is located inside of engine side cover on the
left via mounting bracket. The ECM mainly controls the
following.
• The fuel system control
• The exhaust gas recirculation (EGR) system
control
• The turbocharger system control
• The diesel particulate defuser (DPD) system
control
• The preheating (glow) system control
• The exhaust brake system control
• The power take off (PTO) system control
• On-board diagnostics for engine control
The ECM constantly observes the information from
various sensors. The ECM controls the systems that
affect vehicle performance. The ECM performs the
diagnostic function of the system. The ECM can
recognize operational problems, alert the driver
through the malfunction indicator lamp (MIL), and store
diagnostic trouble codes (DTCs). DTCs identify the
system faults to aid the technician in making repairs.
LNW76ESH000301
CAUTION
To avoid electric shock;
Set the key switch to the "OFF" or "LOCK"
position before checking or repairing the
computer, wiring or/and connectors.
LNW76ESH001001
CAUTION
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