On the above mentioned vehicles the alternator control light may illuminate even though the battery voltage and alternator voltage are correct. At the same time the fault code B1517 (03) is saved in the control unit. This code signifies "Battery voltage below nominal value".
A "software bug·" may be the cause of this problem.
The control unit may react excessively "sensitively". In case of a customer complaint, the battery and alternator should be checked. If no faults are found, the software can be updated to rectify the problem.
Important safety note
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