Electronic control unit

The fuel system electric - electronic circuit comprises a wiring circuit, an electronic unit (control unit) and the following sensors and actuators:

• Rpm sensor
• Coolant temperature sensor
• Air flow meter (debimeter)
• Intake air temperature sensor
• Injector with controls
• Accelerator lever position sensor
• Fast idle control solenoid
• Preheating control unit

Electronic control unit

The electronic control unit (ECU) is located beneath the glove compartment (right hand side) and is connected to the wiring by a 25 pin connector. This receives all the data on engine service conditions transmitted by the various sensors in addition to atmospheric pressure information obtained by a sensor located inside the control unit. The control unit uses this data in conjunction with specific programs to implement the following operating strategies:

• injection advance control
• fast idle control
• exhaust gas recirculation
• glow plug pre/post heating control
• air conditioning system control

INJECTION ADVANCE CONTROL

The electronic control unit uses data on engine rpm/TDC, accelerator lever position, air and coolant temperature and atmospheric pressure to calculate the optimal injection advance. It compares this with the actual value transmitted by the injector with controls and adjusts the advance actuator control solenoid when required.