Ist System (Idle Shutdown Timer); Ist Operation - Navistar International DT 466 Diagnostic/Troubleshooting Manual

7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS

IST System (Idle Shutdown Timer)

Figure 482 Function diagram for the IST system
The function diagram for the IST system includes the
following:
• Electronic Service Tool (EST)
• Intake Air Temperature (IAT) sensor
• ENGINE lamp (red)

IST Operation

The IST is an optional feature that allows the ECM to
shutdown the engine when an extended idle condition
occurs. The idle timer can be programmed for the
customer to automatically shut the engine down for
idle times that range from 2 to 120 minutes.
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
Before engine shutdown, the red ENGINE lamp will
illuminate. The lamp will flash for 30 seconds to warn
the operator the engine is approaching shutdown.
Idle time is measured from last clutch or brake pedal
transition. The engine must be out of gear for the IST
to work.
The IST feature can be programmed to operate at
specific ambient air temperatures, allowing engine
operation in cold or hot weather.
(PTO) applications can be programmed to disable the
IST feature for load levels or when PTO features are
active.
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
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Power Takeoff