| Pos. | Spare part number | Name |
| 1 | - | LIN bus (Local Interconnect Network) |
| 2 | - | Positive battery connection |
| 3 | - | Generator |
A single self-exciting alternator is located in front of the engine, on the left side of the cylinder block. Two alternator options are available for the TD4 engines, depending on the vehicle equipment. One alternator is rated at 90/150 amps, the other at 115/180 amps. The higher rated alternator is used in cold climates, on vehicles equipped with a heated windshield and an electric auxiliary heater. For more information, refer to the chapter: Auxiliary Electric Heater (412-02 Additional Climate Control, Description and Function).
The alternator pulley is equipped with a freewheel clutch to improve NVH (noise, vibration and harshness) characteristics and extend the service life of the accessory drive belt. The freewheel clutch ensures that the belt passes over the pulley without slipping, and prevents the alternator from moving the belt when the crankshaft speed changes due to the high rotational inertia of the alternator internals.
The generator includes the following main elements:
- Stator
- Rotor
- Rectifier
- Voltage regulator
The stator consists of a flat core into which the stator wires are pressed.
The excitation winding is located on the generator rotor. The rotor is enclosed in a stator and mounted on bearings to ensure smooth running and support, taking into account the lateral loads that arise due to the tension of the drive belt.
The rectifier consists of 6 semiconductor diodes placed on a heat sink. The heat sink dissipates the resulting heat generated during electrical processes. The rectifier converts the alternating current generated in the stator coils into direct current, which is required in the vehicle's electrical system.
The regulator provides controlled AC voltage at the generator output. There are two electrical terminals on the generator outer casing. One terminal supplies rectified and regulated DC current from the generator via a large diameter cable to the positive terminal of the battery. The second terminal provides a LIN bus connection between the regulator and the ECM.
The regulator communicates via the LIN bus with the ECM, and the ECM also communicates via the high-speed CAN bus with the CJB (central junction box). The CJB contains software tables that form a mathematical model of the electrolyte temperature and constantly receives information from the ECM about the actual battery voltage. Based on the information received, the CJB transmits via the high-speed CAN bus to the PCM the predicted output voltage that is required from the regulator to effectively charge the battery. The ECM then transmits the appropriate message to the regulator via the LIN bus to achieve the output voltage that is determined in the CJB. This control cycle is repeated in a closed loop.
The LIN bus is also used to transmit mechanical fault and faulty wiring or connector information from the alternator to the ECM. A diagnostic trouble code is generated and stored in the ECM and, if necessary, the charging indicator lamp in the instrument cluster illuminates after a short delay.
During engine cranking, the charge indicator lamp on the instrument cluster comes on when the ignition is activated and goes out when the engine starts and the ECM detects the presence of generator output voltage.
Vehicles equipped with the Stop/Start system - starting from 2010 MY
(The text of the article was taken from the website: «www.LRman.ru»)
Due to the additional loads on vehicles with Stop/Start, a 180 A alternator is used. For more information, refer to the chapter: Starting System (303-06C Starting System - 2.2L Duratorq - Td4, Vehicles Built from 03/2009, Description and Function).
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