Terex TA35, Operation, Safety, Maintenance Manual

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DDEC III & IV Description
1. Electronic Control Module (ECM) - Receives electronic inputs from the driver
as well as from mounted sensors that provide information electronically, such as
oil pressure and temperature and intake manifold pressure. This information is
used to control both the quantity of fuel injected and injection timing.
2. Programmable Read Only Memory (PROM) - Located in the ECM and
encoded with the operating software. Additional information is programmed into
the EEPROM. This information controls the horsepower rating, torque curve,
maximum engine speed and engine protection devices. The ECM processes this
information and sends electronic signals to the Electronic Unit Injectors (EUI)
where the precise amount of fuel is injected into the engine.
3. Electronic Unit Injectors (EUI) - The EUI is a lightweight, compact unit that
injects diesel fuel directly into the combustion chamber. The amount of fuel
injected and the beginning of injection timing is determined by the ECM. The
ECM sends a command pulse which activates the injector solenoid.
The EUI performs four functions:
a - Creates the high fuel pressure required for efficient injection.
b - Meters and injects the exact amount of fuel required to handle the load.
c - Atomizes the fuel for mixing with the air in the combustion chamber.
d - Permits continuous fuel flow for component cooling.
Electronic unit injectors are self compensating and virtually eliminate engine
tune-ups.
Note: Never apply 12 or 24 volts directly to terminals on the injector or engine
sensors as they will burn out. Before removing injectors, the fuel passages
must be blown out to prevent fuel flow from entering the cylinder head.
Courtesy of Machine.Market