7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS 497
IST System (Idle Shutdown Timer)
Figure 482 Function diagram for t
he IST system
The funct ion diagram for the IS
T system includes the
following:
• Electronic S ervic e Tool (ES
T)
• Intake Air Temperature (IAT
)sensor
• ENGINE lamp (red)
IST Operation
The IST is an optional feat
ure that allows the ECM to
shutdown the engine when
an extended idle condition
occurs. The idle tim er ca
nbeprogrammedforthe
customer to automatica
llyshuttheenginedownfor
idle time s that range
from 2 to 120 minutes.
Before engine shutdown, the re
dENGINElampwill
illuminate. The lamp will fl
ash for 30 seconds to warn
the operator the engine is a
pproaching shutdown.
Idle time is me asured from
last clutch or brake pedal
transition. The engin e m
ust be out of gear for the IST
to work.
The IST feature can be pro
grammed to operate at
specific ambient air te
mperatures, allowing engine
operation in cold or h
ot weather. Power Takeoff
(PTO) ap p lications
can be programmed to disable the
IST feature for load
levels or when PTO features are
active.
EGES-270-1
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
To Next Page
Loading...
Need help?
General