Electrical Equipment System — General Information (Mercedes-Benz Sprinter 903)

The cars are equipped with a 12 V electrical system. The "mass" of the car (neutral wire) connected to the negative terminal of the battery, which is generally maintenance-free.

To start the engine, a starter with forced engagement of the gear is used. The starter switch is part of the ignition switch, and when its contacts are closed, the starter traction relay is activated. The generator power produced by Bosch on all models is 120 A.

The generator is driven by a belt from the crankshaft. An electromechanical regulator located on its back cover regulates the charging current.

The control lamp in the instrument cluster serves to determine the serviceability of the generator and voltage regulator.

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