Icp Sensor (Injection Control Pressure) - Navistar International DT 466 Diagnostic/Troubleshooting Manual

7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS

ICP Sensor (Injection Control Pressure)

Figure 461 Function diagram for the ICP sensor
The function diagram for the ICP sensor includes the
following:
• ICP sensor
• Electronic Control Module (ECM)
• Injector Drive Module (IDM)
• Fuel injector
• Injection Pressure Regulator (IPR)
• ENGINE lamp (amber)
Function
The ICP sensor is a Micro Strain Gauge (MSG)
sensor. The ICP sensor is under the valve cover,
forward of the No. 6 fuel injector in the high-pressure
oil rail. The engine harness connection on the valve
cover gasket for the ICP sensor is left of the No. 6
injector connector. The ECM supplies a 5 V reference
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
signal which the ICP sensor uses to produce a linear
analog voltage that indicates pressure.
The ICP sensor provides a feedback signal to the
ECM indicating injection control pressure. The ECM
monitors ICP as the engine is operating to modulate
the IPR. This is a closed loop function which means
the ECM continuously monitors and adjusts for ideal
ICP determined by conditions such as load, speed,
and temperature.
The ECM monitors the ICP signal to determine if the
performance of the hydraulic system is satisfactory.
During engine operation, if the ECM recognizes that
the ICP signal is greater or less than the value that
the IPR is trying to achieve the ECM will set a DTC
and illuminate the amber ENGINE lamp.
The ICP signal from the ECM is one of the signals the
IDM uses to command the correct injector timing.
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
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