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System Overview

GENERAL 

Fig 1: Freewheel Generator
GLL103081Courtesy of VOLVO CARS CORPORATION

The purpose of the generator (GEN) is to supply the power consumers with power and to ensure that the battery remains charged. The generator (GEN) is mounted on the front edge of the engine.

The power handling capacity of the generator (GEN) depends on the engine speed (RPM). When the engine is idling the generator (GEN) only supplies approximately half the maximum power handling capacity. When the engine is idling with many power consumers connected battery recharge is negatively affected i. e, the battery does not charge. Battery charging is less efficient in cold conditions than at room temperature. This means that when the engine is idling for a long time, with large power consumers connected the battery can drain.

If the generator fails to charge the power consuming components will take their supply exclusively from the battery. In the end this will drain the battery completely.

The generator (GEN) first generates AC current which is converted to DC current in the DC bridge. the generator (GEN) has a built-in charge regulator.

The auxiliaries belt transfers power from the crankshaft pulley to the auxiliaries such as the power steering pump, air conditioning (A/C) compressor and generator (GEN). The belt tension is tensioned using an automatic belt tensioner. The belt is a Poly-v-belt.

The generator (GEN) with charge regulator can be diagnosed through the central electronic module.