Component description for the alternator - GF15.40-P-2000A

WARNING: This page does not describe the selected car, but rather 28 other vehicles, including the 2012 Mercedes-Benz GL550, 2012 Mercedes-Benz GL450, 2011 Mercedes-Benz ML63, 2011 Mercedes-Benz ML550, and 2011 Mercedes-Benz ML350. However, it is still accessible from the selected car via links, so may be relevant.

ENGINE 113 in MODEL 164 only valid with engine control unit variant ME 2.8

ENGINE 272 in MODEL 164 only valid with engine control unit variant ME 9.7

ENGINE 629 in MODEL 164 only valid with engine control unit variant CDI 5

ENGINE 642 in MODEL 164 only valid with engine control unit variant CDI 4

Fig 1: Identifying Alternator Components

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Assignment of connection for signal lines

Connector on alternator, pin 1:

Alternator with multifunctional regulator without interface: Connection for alternator (G2) to driver-side SAM control unit with fuse and relay module (N10/1)
Alternators with bit synchronous data interface (BSS): Connection for alternator to engine control unit ME (N3/10) or CDI (N3/9)
Alternators with local interconnect network interface (LIN): Connection for alternator to engine control unit ME or CDI

Connector on alternator, pin 2:

This is a Dynamo Field Monitor (DFM) signal. It provides information about the load condition of the alternator.
This signal is used for electrical control of the engine heater booster. In model series 211 the AAC [KLA] control and operating unit (N22) evaluates the signal and regulates the heater booster (R22/3) depending on the alternator load.

Pre-excitation power circuit

Alternators receive the pre-or excitation current directly from the battery (G1), via circuit B+ at the alternator. The switch-on signal at Pin 1 of the alternator takes place:

for multifunction regulator without interface with a discrete signal from the driver-side SAM control unit with fuse and relay module
for BSS or LIN interface with a valid message from the engine control unit

Excitation power circuit

Alternator are self-exciting power generators. The excitation current builds up the magnetic field in the excitation coil of the rotor. It is branched off from the current flowing in the three-phase AC winding.

Charge power circuit

The charge power circuit supplies the on-board electrical system with electrical energy.

Control

Regulation of alternator with multifunction regulator takes place by integral electronics depending on the rotational speed and on-board power supply voltage.

For alternators with BSS or a LIN interface the engine management intervenes in the regulation.

Overview of system components On-board electrical system power supply

GF15.40-P-9999A