Fan is close to $400 - $500+ depending on the manufacturer. Plus 3-4 hours to remove and replace. Before shelling out that kind of money and time I would make sure it the fan and not something else.

If you want to DIY it you can purchase and install BMW Scanner 1.4 to use in your diagnostic of the [problem. Hopefully you're not an Analog guy living in a digital world like some other owner on this forum.

I would confirm that you have power to the fan, the fact that it is very hard to snap in could be that the wires got really hot one time and might had melted something. It's best to start with the easy stuff and go onto the harder stuff.

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2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
Lotus Europa 1970 Destroyed by fire
Lotus Europa 1970 S2 Renault Powered
Lotus Type 52 1970 Twincam Webers Powered
PORSCHE 911 Targa 1982 The Garage Queen
Audi Avant donated to Kars for Kids
BMW 525IT Sold
Audi 4000CS Quattro Sold
Jensen Healey Lotus Powered Sold
Opel 1900 Sold
Triumph Spitfire 1971 Sold
Triumph Spitfire 1968 Sold
Plymouth "Cuda" 340 Six pack SOLD