[khomer2]

Why is my 2005 mercedes c230 kompressor’s cooling fan going so fast and then when i press the auto on the ac it goes even faster, i changed out the pressure switch and still nothing help please i dont know if this is a good or bad thing

Welcome to BW texastoast30,

Good to have you as a new member.
Please complete your BW registration profile so members may better assist you.
Goto your ===> user CP profile====> click on your icon----> click on Account Settings----> goto Account Details----> add vehicle details---->
ADD your make model YEAR into your Profile ----> click save.

Moving you along, over to the w203 forum.

 

[rudeney]

The engine suction fan speed is controlled electronically based on demand. It will always run when the AC is on, faster when cooling demands rise. It will also run fast when the coolant temperature rises above 90C.

 

[texastoast30]

Yes sir thank you, but i noticed that when i changed the a/c compressor the fan started going faster than normal and on the button inside the car labeled auto when i press it the fan goes really fast it sounds like a plane is about to take off

 

[texastoast30]

I also put a shop fan in front of the radiator and the fan slows down

 

[rudeney]

Is it very hot outside and is your AC running on "max"? If so, the fan is doing what it's supposed to - draw as much air possible across the condenser for maximum cooling.

 

[texastoast30]

I could have it in the garage start it up a the fan kicks on like normal then i put it on a/c setting at three and the fan takes off and i can press the auto button a the very start and it sounds like a plane taking off and really loud

 

[rudeney]

That actually may be normal. The fan speed is adjusted according to demand. When you say the AC is set on "three" do you mean the fan speed? It's more the needs of cooling to reach the set temperature that is the issue. It's a function of outside ambient temp and cabin temp.