Alternator - Charge Lamp Comes ON While Driving

SI B 12 22 05
Engine Electrical Systems

November 2005
Technical Service

This Service Information bulletin supersedes S.M. B12 215 05 dated June 2005

SUBJECT
Charging Indicator Lamp Illuminates While Driving

MODEL
Vehicles equipped with a 120 or 140 Amp Valeo alternator only.
E36 (Z3 roadster and Z3 coupe) equipped with M54 engine
E36 (M roadster and M coupe) equipped with S54 engine
E39 (5 Series) equipped with M54 engine
E46 (3 Series) equipped with M54 engine
E46 (M3 coupe and convertible) equipped with S54 engine
E53 (X5) equipped with M54 engine

SITUATION
The customer complains the charge indicator lamp illuminates while driving.

CAUSE
A faulty diode in the alternator regulator is activating the charging lamp. Although the light is illuminated the vehicles charging system continues to charge and battery state is not affected.





PROCEDURE
Do not replace the alternator. On a customer complaint basis only replace the voltage regulator using one of the parts listed.

PARTS INFORMATION
Vehicles equipped with Valeo 120 or 140 Amp alternators only. The current version of EPC is incorrect and will be corrected shortly, please install proper part number listed.

WARRANTY INFORMATION
Covered under the terms of the BMW New Vehicle Limited Warranty.
Refer to KSD for proper defect code and labor allowance for work performed.