I just recently purchased my FIRST E30. A 1991 318i sedan from a local fella.
One of the main selling points for the car was that it had a freshly redone AC system which blows ice cold air (and it truly does), which is an absolute necessity around here during the hot muggy summer months.
The problem I am having is with the AC controls.
Starting point of the AC system before the car is turned on:

1. Blower speed is at "0" (blower motor OFF).
2. Temperature is at the coldest setting.
3. "AC" button (the one that engages the compressor) is OFF.
4. "Re-circulation" button is ON.
5. Middle slider (one that blows air on your face) is all the way to the right (OPEN). The other two sliders are all the way to the left (CLOSED).
At this point, when I turn on the car what SHOULD happen, according to my years of experience in driving regular automobiles with perfectly working AC's, is.... nothing.
Because the blower motor speed is set to "0". No air should be pumped into the cabin. Furthermore, since the re-circulation button is ON, even if I drive the car, there should be no residual air coming into the cabin since all the flaps and whatnot should be closed, securing the cabin in terms of outside air coming into the cabin through the vents.
HOWEVER!
What actually happens when I turn my car on is that the blower motor starts spinning and blows air into the cabin.
VIDEO (Please watch with earphones/headphones with volume turned up so you can hear the minute noises that I am referring to.

0:11 - ignition turned to "accessory" (engine not ON); blower motor kicks on and air starts to blow into the cabin
0:23 - blower speed changed to "1"; notice the slight pitch change in the blower motor indicating slightly higher RPM
0:25 - blower speed changed to "0"; pitch changes again to lower pitch but still does not turn off and blows air
0:28 - blower speed changed to "1"; pitch changes again to higher pitch
0:31 - blower speed changed to "0"; pitch changes again to lower pitch but still does not turn off and blows air
0:36 - close-up video of air vents to let you hear the air coming out
0:37 - blower speed changed to "1"; pitch changes again to higher pitch
0:40 - blower speed changed to "0"; pitch changes again to lower pitch but still does not turn off and blows air
0:43 - blower speed changed to "1"; pitch changes again to higher pitch
0:46 - blower speed changed to "0"; pitch changes again to lower pitch but still does not turn off and blows air
0:50 - re-circulation turned OFF; blower motor stops spinning and stops blowing air into the cabin; you can hear the servo motors engaging the flaps to open them but the motor does not stop and you can hear the motor continue to whir/buzz in the background
1:07 - re-circulation turned ON; blower motor comes back on and blows air into the cabin
1:10 - close-up video of air vents to let you hear the air coming out again
1:13 - re-circulation turned OFF; whirring/buzzing noise from re-circulation flap motor is back and can be heard
1:24 - re-circulation turned ON; blower motor comes back on and blows air into the cabin
1:30 - "AC" button turned ON; activates the electric fan in the engine bay
1:38 - "AC" button turned OFF; electric fan shuts off
1:45 - engine started
1:54 - "AC" button turned ON; compressor is engaged and cold air starts to blow into the cabin (keep in mind the blower speed is still set at "0" at this point. There should be no air coming into the cabin even if the "AC" button is turned ON)
2:02 - "AC" button turned OFF; compressor is disengaged and regular cabin air gets re-circulated by the blower motor (which again should not be on since the blower speed is still set at "0")
2:06 - "AC" button turned ON; compressor is engaged and cold air starts to blow into the cabin
2:12 - "AC" button turned OFF; compressor is disengaged and regular cabin air gets re-circulated by the blower motor
2:14 - re-circulation turned OFF; whirring/buzzing noise from re-circulation flap motor is back and can be heard
2:24 - "AC" button turned ON; whirring/buzzing noise from re-circulation flap motor is back and can be heard while the compressor is engaged and cold air starts to blow into the cabin
SO!
Basically, whenever I have the re-circulation ON, the blower motor turns on even if the blower setting is set to "0". When I turn the re-circulation OFF, then the whirring/buzzing noise comes on from the flap servo motor.
So it comes down to, would I rather have the air always blowing in my face (blower motor ON) or listen to that annoying whirring noise.
Anyone have ANY idea what this is being caused by?
One of the main selling points for the car was that it had a freshly redone AC system which blows ice cold air (and it truly does), which is an absolute necessity around here during the hot muggy summer months.
The problem I am having is with the AC controls.
Starting point of the AC system before the car is turned on:

1. Blower speed is at "0" (blower motor OFF).
2. Temperature is at the coldest setting.
3. "AC" button (the one that engages the compressor) is OFF.
4. "Re-circulation" button is ON.
5. Middle slider (one that blows air on your face) is all the way to the right (OPEN). The other two sliders are all the way to the left (CLOSED).
At this point, when I turn on the car what SHOULD happen, according to my years of experience in driving regular automobiles with perfectly working AC's, is.... nothing.
Because the blower motor speed is set to "0". No air should be pumped into the cabin. Furthermore, since the re-circulation button is ON, even if I drive the car, there should be no residual air coming into the cabin since all the flaps and whatnot should be closed, securing the cabin in terms of outside air coming into the cabin through the vents.
HOWEVER!
What actually happens when I turn my car on is that the blower motor starts spinning and blows air into the cabin.
VIDEO (Please watch with earphones/headphones with volume turned up so you can hear the minute noises that I am referring to.

0:11 - ignition turned to "accessory" (engine not ON); blower motor kicks on and air starts to blow into the cabin
0:23 - blower speed changed to "1"; notice the slight pitch change in the blower motor indicating slightly higher RPM
0:25 - blower speed changed to "0"; pitch changes again to lower pitch but still does not turn off and blows air
0:28 - blower speed changed to "1"; pitch changes again to higher pitch
0:31 - blower speed changed to "0"; pitch changes again to lower pitch but still does not turn off and blows air
0:36 - close-up video of air vents to let you hear the air coming out
0:37 - blower speed changed to "1"; pitch changes again to higher pitch
0:40 - blower speed changed to "0"; pitch changes again to lower pitch but still does not turn off and blows air
0:43 - blower speed changed to "1"; pitch changes again to higher pitch
0:46 - blower speed changed to "0"; pitch changes again to lower pitch but still does not turn off and blows air
0:50 - re-circulation turned OFF; blower motor stops spinning and stops blowing air into the cabin; you can hear the servo motors engaging the flaps to open them but the motor does not stop and you can hear the motor continue to whir/buzz in the background
1:07 - re-circulation turned ON; blower motor comes back on and blows air into the cabin
1:10 - close-up video of air vents to let you hear the air coming out again
1:13 - re-circulation turned OFF; whirring/buzzing noise from re-circulation flap motor is back and can be heard
1:24 - re-circulation turned ON; blower motor comes back on and blows air into the cabin
1:30 - "AC" button turned ON; activates the electric fan in the engine bay
1:38 - "AC" button turned OFF; electric fan shuts off
1:45 - engine started
1:54 - "AC" button turned ON; compressor is engaged and cold air starts to blow into the cabin (keep in mind the blower speed is still set at "0" at this point. There should be no air coming into the cabin even if the "AC" button is turned ON)
2:02 - "AC" button turned OFF; compressor is disengaged and regular cabin air gets re-circulated by the blower motor (which again should not be on since the blower speed is still set at "0")
2:06 - "AC" button turned ON; compressor is engaged and cold air starts to blow into the cabin
2:12 - "AC" button turned OFF; compressor is disengaged and regular cabin air gets re-circulated by the blower motor
2:14 - re-circulation turned OFF; whirring/buzzing noise from re-circulation flap motor is back and can be heard
2:24 - "AC" button turned ON; whirring/buzzing noise from re-circulation flap motor is back and can be heard while the compressor is engaged and cold air starts to blow into the cabin
SO!
Basically, whenever I have the re-circulation ON, the blower motor turns on even if the blower setting is set to "0". When I turn the re-circulation OFF, then the whirring/buzzing noise comes on from the flap servo motor.
So it comes down to, would I rather have the air always blowing in my face (blower motor ON) or listen to that annoying whirring noise.
Anyone have ANY idea what this is being caused by?
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