Fan regulator: the command and flow are different

In a few sentences

In brief

The electronic module is involved in speed control.

Useful to know

The internal fan regulator controls its operation according to the system. HELLA regarded it as a separate part of the motor itself and of the resistor performances. [1]

The degree set on the panel is not an independent measurement of the real flow through all the air ducts. Upon complaint, specify whether the setting changes, whether the motor reacts and where the air is felt. This helps to distinguish between a control, electrical and air problem. Do not order a module just because some speed is missing; a check of the specific circuit is required.

Sources

For further detail and to check the information:

[1] HELLA — interior blower regulators ↗