Installation Manual

Electrical & Electronic Application And Installation Manual
Production Release Version 1.0
Page 11
2.0 Engine & Aftertreatment Component Overview
2.1 Main Engine Sensor and Actuator Detail
2.1.1 Electronic Control Module
The A5:E2v2 & A5:E12 ECMs are electronic control devices that govern
engine speed, torque output and manage the engines performance and
emissions via a number of sensors and actuators. The Engine ECM is
supplied with each engine and the variant is dependent upon the system
voltage selected. The ECM is situated on the left hand side rear of the
engine. The device has two connection sockets, one for the engine wiring
harness (J2) and the other for the OEM machine wiring harness (J1). Two
versions of the A5:E2v2 ECM are available a fuel cooled and air cooled, the
choices of which depends upon the maximum ambient temperature the unit
will be exposed to (see mechanical installation guide for details of fuel system
connection requirements and temperature restrictions).
2.1.2 Fuel System
The engine fuel system comprises of an electronic lift pump, high pressure
fuel pump, electronically controlled unit injectors and a High pressure fuel rail
to feed the injectors. The electrical lift pump is used to provide a constant flow
of fuel to the engine fuel pump. This pump also provides the user with an
electrical priming feature. The fuel pump provides high pressure fuel to the
fuel rail. The engine ECM via the fuel pump solenoid controls this fuel pump
delivery and the resulting rail pressure. The engine ECM controls the fuel
pump solenoid control based upon the inputs received from the fuel
temperature sensor (which enables the control to be tailored to the specific
fuel characteristics) and the fuel rail pressure sensor (which measures the
actual pressure within the fuel rail).
Note: for more information regarding the electrical fuel lift pump and
priming feature please see the mechanical A&I Guide and section 6.3 of
this document for electrical installation requirements.
High pressure fuel is delivered to each of the electronically controlled unit
injectors which when activated by the engine ECM deliver a controlled
measure of fuel for combustion. Voltages applied by the ECM to activate the
injectors are high around 70V and the OEM must ensure that any systems
sensitive to electromagnetic radiation are not close proximity to the harness
components that lead to the injectors.
The engine fuel system is also fitted with a water in fuel switch mounted within
the primary filter bowl. This switch is mandatory for all Tier 4 engines to
indicate to the operator that the filter water trap is full and needs emptying.
This switch is supplied with the engine from the factory but it is the customer’s
responsibility to connect this component to the ECM J1 connector via the
machine wiring harness.