Hi:

I just bought an '04 CLK 500 cabrio. 31k miles, seven months to go on 4/50 factory warranty so I'm hoping to catch everything in the next seven months ;-) I'm due for Service B in 2500 miles, and my local dealer said that '04 and prior years had Service A and B included in warranty work.

I live in AZ, so you know it's hot. Very hot. 100+ for six months of the year (no dry heat quips,
please). I drove the car from L.A. to Phoenix last week, and it ran like a champ. Around town here, when the fan kicks on (the AC runs non-stop, as you can imagine), it literally sounds like an airplane engine. It's audible from hundreds of feet away.

I called the dealer just to ask a few questions, and one was about the fan noise. He acknowledged that it was very loud, but normal, nonetheless. I have read a few posts on forums when researching this issue, and it seems to be a not-uncommon occurance. The water temp is OK, regardless of outside temperature. The service mgr. said that the sensor measures the under hood temp, not merely the water temp, and activates the fan accordingly.

These days, we have temps in the low 100s -- which is to say between 100 and 110. Single-digit humidity. So just siting outside, the temp under hood will be high. Yes, the car is black, to make matters worse.

So before I accept whatever the service manager tells me about the fan noise when I bring the car in for the Service B, I'm wondering if others in this forum have the same noisy fan. If so, what has been your course of action, or is it just SOP? It seems way out of line for a car of this cost, but then again, quirks are quirks, regardless of price.

I'll appreciate any info on this topic. Thanks in advance.

 

Hi pcohen,

Check your coolant level. If your coolant level is low, your waterpump may be screaming. Thats the only thing I can think of.

Blue

 

Thanks. Will do.

 

Have exactly the same on rare occasions on my wife's '07 CLK 550. Only when it's 90º+, been parked in the hot sun or driven. So loud I thought it was a plane overhead when she pulled into the garage. All temps and coolant levels normal.

 

We should start a club. I'm guessing that you've had this checked out and that there's nothing abnormal?

 

Not checked out yet. Just got finished with the car at the dealer for a week last month, tracing and fixing some minor squeaks. Would like to drive it some now. The loud fan noise happens so rarely the only way they will find it is if the computer can provide a readout. They did a complete computer readout when they were checking for squeaks, but before we got the fan noise. Fluids and temps normal. Could be related to the A/C, because my wife says it stops when she turns off the A/C.

I am going to give it another week, or if it gets more frequent, whichever comes first.

 

Hey new guy here.

I had a similar problem. I'm not sure ours is related but when I turned on my AC full blast it sounded like a jet engine. I called my local mechanic here he said check the AC fan under the dash. It sems MB uses all kinds of foam tape under the dash. That was it. Foam tape was lodged in the fan blade which threw off the balance. Once I took it out it was quite as a mouse.