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Home >> BMW >> 1999 >> 328is Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Performance DME 7.2 - Overview >> DME 7.2 >> New Or Modified Output Control Functions >> E-Box Fan Control
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E-Box Fan Control

The E Box fan is controlled by ME 7.2. The control module contains an integral NTC temperature sensor for the purpose of monitoring the E box temperature and activating the fan.

When the temperature in the E-Box exceeds predetermined values, ME 7.2 provides a switched ground for the E Box fan to cool the E box located control modules.

With every engine start-up, ME 7.2 briefly activates the fan ensuring continued fan motor operation for the service life of the vehicle. This feature is intended to prevent fan motor "lock up" from lack of use due to pitting or corrosion over time.

Fig 1: E-Box Fan Control System Diagram
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