A/C Fan Hyperactive on "Auto"
Thread Starter
Super Member
Joined: May 2003
Posts: 968
Likes: 78
From: Long Island, New York
2018 E400 4matic Wagon
A/C Fan Hyperactive on "Auto"
When the A/C is set to "Auto," the system decides which vent outlets to use and what speed to blow the fan. I've noticed lately that the fan is blowing at a speed that is higher than it should, which produces a lot of noise. I realize I can just control it manually, but Auto does serve a purpose -- it's supposed to blow fast when you first start the car on a hot day, and then gradually slow down after the car has been cooled down.
Does anyone have a clue as to a DIY solution? I don't want to go to the dealer and pay some exorbitant fee to diagnose the issue and then be told it's some ridiculous amount to replace some climate control module.
Thanks.
Does anyone have a clue as to a DIY solution? I don't want to go to the dealer and pay some exorbitant fee to diagnose the issue and then be told it's some ridiculous amount to replace some climate control module.
Thanks.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,225
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
Observe what direction is the air flow.
Quite often defrost (what is default) is taken as high speed as it makes more noise than lower vents.
Is your climatronic showing fan speed?
Quite often defrost (what is default) is taken as high speed as it makes more noise than lower vents.
Is your climatronic showing fan speed?
Thread Starter
Super Member
Joined: May 2003
Posts: 968
Likes: 78
From: Long Island, New York
2018 E400 4matic Wagon
I'm noticing the air coming from the dash vents. When the fan is on Auto, the little screen just reads Auto and doesn't indicate the fan speed. It only indicates fan speed when you adjust the speed manually.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,225
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
Dash vents as side vents, or center vent?
Play with direction adjustment and see if it works.
Quite often disconnected vacuum tubing makes the system going to default.
Play with direction adjustment and see if it works.
Quite often disconnected vacuum tubing makes the system going to default.
