Repair manual

EDC SYSTEM FUNCTIONS
The EDC 7 UC31 electronic center manages the following main functions:
Fuel injection
Accessory functions such as cruise control, speed limiter, PTO and the like
Self-diagnosis
Recovery
It also enables:
Interfacing with other electronic systems (if any) available on the vehicle
Diagnosis
Fuel dosing
Fuel dosing is calculated based on:
- accelerator pedal position
-enginerpm
- quantity of air admitted.
The result can be corrected based on:
- water temperature
or to prevent:
-noise
-fumes
-overloads
-overheating
Pressure can be adjusted in case of:
- engine brake actuation
- external device actuation (e.g. speed reducer, cruise control)
- serious defects involving load reduction or engine stop.
After determining the mass of air introduced by measuring its volume and temperature, the center calculates the corresponding
mass of fuel to be injected into the cylinder involved, with account also taken of gas oil temperature.
Delivery correction b ased on water temperature
When cold, the engine encounters greater operating resistance, mechanical friction is high, oil is till very viscous and operating plays
are not optimized yet.
Fuel injected also tends to condense on cold metal surfaces.
Fuel dosing with a cold engine is therefore greater than when hot.
Delivery correction to prevent noise, fumes or overloads
Behaviors that could lead to the defects under review are well known, so the designer has added specific instructions to the center
to prevent them.
De-rating
In the event of engine overheating, decreasing delivery proportionally to the temperature reached by the coolant changes injection.
54
SECTION 3 - INDUSTRIAL APPLICATION
F3C CURSOR ENGINES
Base - May 2007 Print P2D32C005 E