Perkins 2506 Operation And Maintenance Manual page 31

SEBU8313-02
Failure of Sensors
All Sensors
A failure of any of the sensors may be caused by one
of the following malfunctions:
• Sensor output is open.
• Sensor output is shorted to "- battery" or "+
battery" .
• Measured reading of the sensor is out of the
specification.
Programmable Monitoring System
(PMS)
The Programmable Monitoring System determines
the level of action that is taken by the Engine Control
Module (ECM) in response to a condition that can
damage the engine. These conditions are identified
by the ECM from the signals that are produced from
the following sensors.
Engine Coolant Temperature
Sensor 1
The coolant temperature sensor monitors engine
coolant temperature. The output of the ECM can
indicate a high coolant temperature through a relay
or a lamp. The coolant temperature sensor is used by
the ECM to determine initiation of the Cold Start
Condition.
Sensors and Electrical Components
Failure of the Coolant Temperature
Sensor
The ECM will detect a failure of the coolant
temperature sensor. The diagnostic lamp will warn
the operator about the status of the coolant
temperature sensor. A failure of the coolant
temperature sensor will cause a shutdown of the
engine. The faulty sensor should be replaced. Refer
to Disassembly and Assembly Manual, "Coolant
Temperature Sensor - Remove and Install".
Inlet Manifold Pressure Sensor 3
The inlet manifold pressure sensor measures boost
pressure in the inlet air manifold. A signal is sent to
the ECM. A failure of the inlet manifold pressure
sensor will limit the power of the engine.
Inlet Manifold Temperature Sensor
5
The inlet manifold temperature sensor measures the
inlet air temperature. A signal is sent to the ECM. The
inlet air temperature sensor is also used by the ECM
to determine initiation of the Cold Start Strategy.
Engine Oil Pressure Sensor 7
The engine oil pressure sensor is an absolute
pressure sensor that measures the engine oil
pressure in the main oil gallery. The engine oil
pressure sensor detects engine oil pressure for
diagnostic purposes. The engine oil pressure sensor
sends a signal to the ECM .
Low Oil Pressure Warning
The setpoint for the low pressure warning is
dependent upon the engine speed. The fault will be
active and logged only if the engine has been running
for more than 8 seconds.
Low Oil Pressure
The very low oil pressure setpoint is dependent upon
the engine speed. If very low oil pressure is detected,
the ECM will stop the engine immediately unless
Critical Events Override is active.
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Operation Section