Automatic engine start-stop function: Alternator
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A more powerful alternator is installed in conjunction with the automatic engine start-stop function due to battery discharge during the engine shutdown.
The alternator assumes the following functions during driving:
- Retention of the required level of vehicle voltage
- Supply to all electrical consumers.
The controller regulates the output voltage of the electrically excited alternator with uncontrolled rectifier by applying the excitation current.
The Digital Engine Electronics (DME) controls the alternator by using the following functions:
- Switching the alternator on and off on the basis of defined parameters
- Temperature-dependent maximum permitted power consumption of the alternator
- Calculation of the drive torque and current based on the transmitted controller parameters
- Control of the reaction of the alternator with addition of high power consumers (load-response function)
- Diagnosis of the alternator and the data line between alternator and engine control unit
- Storage of any faults that occur on the alternator in the fault memory of the engine control unit
- Activation of the charge indicator light in the instrument cluster (KOMBI) when a fault is identified.