Cooling System - Auxiliary Cooling Fan Noisy
GROUP 64Heating and Air Conditioning
64 02 02
Woodcliff Lake, NJ
Service Engineering
May, 2002
SUBJECT
E39; Electric Auxiliary Fan (Gen2) Noisy
MODEL
E39 produced from 01/01 up to 09/01
SITUATION
After the "Auxiliary Electric Fan Recall" (01-V-206) has been performed on a vehicle, the customer may complain about "noisier" operation of the new fan (Gen2 unit; PN 64 54 6 921 395).
CAUSE
Electric fan exceeds speed tolerances in its lower speed ranges (at 5% to 25% of activation).
Important Notes:
Generation 2 auxiliary fans (introduced into production in 01/01), are designed to have higher nominal speeds (at the same activation stage), than the previous Generation 1 units. This is due to higher fan efficiency and is a normal behavior.
However, in some cases, Gen2 fan speed (especially with low PWM activation) can exceed the limits, causing vibration in a range of resonance frequencies.
CORRECTION
On a customer complaint basis, and only after comparing an affected vehicle with another Gen2 fan equipped E39 vehicle, replace the auxiliary fan with a Gen1 unit (PN 64 54 6 921 946)
PROCEDURE
For replacement instructions refer to repair instruction RA 54 11 000, found in BMW Technical Information System (TIS).
PARTS INFORMATION
Part Number Description Quantity
64 54 6 921 946 Auxiliary 1
electric fan GN1
WARRANTY INFORMATION
Covered under the terms of the BMW New Vehicle Limited Warranty.