Very high temperatures are generated in the E box. One cause is heating from the engine compartment, another is the power loss of the control units in the E box.
As electronic control units can only be operated in a restricted temperature range, the E box requires a cooling facility. The permitted component temperatures must not be exceeded. As very much higher temperatures can occur in locally in the control units, the air temperature in the E box must be kept as low as possible. The lower the temperature, the longer the expected service life of electronic components.
These problems are solved using a fan for the air circulation in the E box. The use of the E-box fan now achieves two ends:
-The air circulation reduces the air temperature in the E box
- The generated air movement cools hot positions on the control units. This prevents local excess temperatures.