The blower final stage fan resistor is known to fail. Symptoms are the heater fan speed varies regardless of the setting, the fan will not turn off when the car is switched off, or the fan will not switch on at all.
Average mileage: 100,972 (900–219,726)
39 people reported this problem
Fan not blowing when the heart or air condition is on.
The air conditioner would work, and you could tell it was cold but the air would not blow out of the vents. Also this would happen off and on for about 6 months. The air conditioning would work and blow cold air, then it seemed like on the really HOT days it would not blow the cold air at all, so i had enough!!! Replaced the final stage transistor and Yeah that fixed the problem!!!!!!!!!!!
Blower intermittently would shut off, and fan speed was sporadic. So I opened the FSU or (final - stage - resistor unit) to find that one of the prongs to the main power connector was shorting causing the prong to partially disconnect from the circuit board. Possibly moisture could have been the cause!
Blower Final Stage Fan Resistor May Fail on BMW 328i
A/C starts and stops unpredictably as if a connection is loose.
Perhaps I will have to try replacing the final stage fan transistor whatever that is.
Blower goes on intermittently. They want to replace whole resistor for $400+
Taking to the dealer on Monday.
sometimes fan doesnt work
the a/c would turn on when it wanted,first i thought it was a loose connection point, wrong! I'm now going to replace the final stage resistor, pray to god. I live in Las Vegas, and it's HOT!!!!!
I purchased my 328i in 2012 with 9,000 miles on it. I've had it now for 4 years and really enjoy the smooth ride. However, this week my ac won't turn on at all. I see that this seems to be a frequent problem with other owners of the 328i. I'm really disappointed. I thought that buying a high end car like a BMW would at least be problem free before 50,000. I've had a few recall parts replaced and I have to say the service department was great. I now have to make an appointment to find out if the problem is the final stage resistor like the other 38 people who've posted. I hope it doesn't cost too much. Not sure if I'll be purchasing another BMW.
Same issues. Replaced my resistor just over 14months ago and now i need to replace it again.
Air and heat blower is doing its own thing. It goes high to low constantly. The biggest problem is that it stays on after the car is shut off.
No a/c and heater coming out.
Neither the heater or A/C is blowing air. I live 150 miles from the dealership and what really irks me is that I only have 900 miles on the car!
Air shuts off when after being driven for a couple of hours. Then will come back on after a while.
Air conditioner on but no air blowing. Brand new wagon.
Air suddenly stopped coming out of vents one day. Sounds like it is trying to work but nothing comes out. My dad looked at the gauges inside to test them and as he put them back, ready to try something else, it suddenly started to work. By the next day, it wasn't working again.
the fan does not blow at all for the air conditioner or the heat, I am taking it to the dealer on Monday. Im hoping they will say its covered under warranty.
The AC fan blows at random speeds without being touched. The air coming out is cold, but set on maximum, it will blow hard and then soft then somewhere in the middle and fluctuate the entire time you are driving.