display BMW 645Ci COUPE 2002 E63 N62B44 Engine Workshop Manual

Downloaded from www.Manualslib.com manuals search engine The ECM takes on the following functions:
• Activation/deactivation of the alternator.
• Informing the alternator regulator of the nominal voltage value to be set.
• Controlling the alternator's response to load.
• Diagnosing the data line between the alternator and the ECM.
• Storing alternator fault codes.
• Activating the charge indicator lamp in the instrument cluster.
The connection with the ECM makes it possible to equalize the alternator load torque for
nearly all operating conditions. This supports the engine idling speed control and the bat-
tery load balance. In addition, the ECM receives information from the Power Module about
the battery's calculated temperature and charge status. This means that alternator output
can be adapted precisely to the temperature and load status of the battery which increas-
es the battery service life.
The charge indicator display strategy has not changed in comparison with the alternators
currently in use. Regulating the alternator output is particularly important when activating
Valvetronic operating motors.
A temperature protection function is implemented in the voltage regulator. If the alternator
overheats, the alternator voltage is reduced until an appropriate temperature has been
reached.
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• Mechanical faults such as blockages or belt drive failure.
• Electrical faults such as exciter diode defects or over/under voltage caused by regula-
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• Connection defects between the ECM and the alternator.
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N62 Engine