GF07.61-P-3023CY Fan Control, Function

GF07.61-P-3023CY Fan Control, Function
- up to model year 08

The ME-SFI [ME] control unit (N3/10) indirectly actuates the combustion engine and air conditioning with integrated control fan motor (M4/7).
The fan specified speed is transmitted by the ME-SFI [ME] control unit via a pulse width modulated signal (PWM signal). The duty cycle of the PWM signal is 10 to 90 %.

Meaning:
10% Fan motor "OFF"
20% Fan motor "ON", minimum rotational speed
90% Fan motor "ON", maximum rotational speed

If the actuation is faulty, the fan motor rotates at maximum rotational speed (fan emergency mode).

The automatic air conditioning control and operating unit (N22/7) transmits the status of the automatic air conditioning to the ME-SFI [ME] control unit via the interior CAN (CAN B) and chassis CAN (CAN E). The fan specified speed is dependent on this and on the coolant temperature.

The fan motor continues running for up to 5 minutes after ignition "OFF" if the coolant temperature, the engine oil temperature (from the temperature model) or the temperature of the ME-SFI [ME] control unit exceeds specified maximum values.
If the battery voltage drops excessively during this operation, engine- off running is suppressed.