CDI control module

Engine OM 642 is equipped with the CR 4 electronic engine control in model series 164 and 251. Model series 211 is fitted with the CR 5 electronic engine control. The primary function of the electronic engine control is to regulate the common rail injection. It is also incorporated into the network of other electronic control modules via the class C CAN bus. It actuates the alternator and the glow control module over a LIN bus. The control module is located in the engine compartment next to the fuse box.

One of the main functions of the electronic engine control module is to regulate the common fuel rail injection:

• The injection timing point and injection quantity are regulated by actuation of the piezo actuators.
• The injection pressure in the fuel rail is regulated by actuation of the pressure regulator valve or the quantity control valve.

It also controls the delivery rate of the high pressure pump.

 

The functions associated with fuel injection also include:

• Idle speed control
• Smooth running control
• Mass air flow based quantity mean value adaptation for the injection quantity
• Smooth operation-based minimum quantity drift compensation

The CDI control module also performs other functions:

• Rpm limitation
• Overrun fuel shutoff
• Fuel rail pressure regulation
• Air control
• Drive control
• Diagnosis