mleskovar

Not that I know of.

mcheung

This is a great thread!

Mine is a 2003 C320. Air is not blowing through the passenger side footwell no matter how I set the blowing position. Would this be the footwell stepper motor and/or the flapping actuator and/or the flap linkage?

Would the procedures described in page 1 of this thread help me get to the part(s) I need to replace?

Also, it looks like air always blow through the center vents, i.e., not the vents toward the windshield and not the vents at the footwells, but the 4 vents in the center where you can adjust the blowing angles. If you set the blowing position to the windshield or footwell, only less air is coming through the center vents, as opposed to no air. Is that normal? I remember it wasn't the case before. But I am not 100% sure.

Thanks.

mleskovar

Yes.

If you have a thumbwheel in the center of those vents then it's for adding outside/'fresh' air to the mix. If you leave the vent open to outside air it will always allow air through.

mcheung

Thanks, mleskovar.

I hope this is the only problem. Air wasn't blowing from any of the vent when I turn on the fan/AC, until half a minute or so later. It had been like that for a while. If I tilted open the sunroof or open the window to "force" more airflow, air would start blowing a little sooner. Then about two months ago, there was a flapping noise when the car started. It flapped for about 30-40 seconds, then it went away. It seemed to come from somewhere right below but behind the radio. Then I noticed it took longer for air to blow through the vents after I turn the fan/AC on, perhaps after a minute or two. Now there's no more flapping noise. But the fan delay problem is still there.

I came across this post and tried the "Defrost"+"Circ" reset. The lights never stop blinking. Then I determined it's the footwell vent on the passenger side having problem.

Do you think it's just the footwell stepper motor/flapping actuator/the flap linkage problem? or could it be something else that cause air not blowing when I turn on the fan/AC, until a minute or two later?

The dealer quoted me 6 hours labour + stepper motor ($400) to fix the flapping noise. It's a lot of money. I really want to see if I can fix it myself.

mleskovar

Your symptom.....flapping noise (like a book closing? )...sounds like the linkage. Do both sides if you go in there.

It's usually the plastic linkage (that's been strengthened) that goes. Motor should be $100. I think all the linkage is packaged together now....get one of those. Get a motor if if will make you feel better but don't crack open the box unless you really need it as it won't be returnable (electric part).

Give it a try, we'll be here. Just follow the directions closely and be patient. Give yourself a lot of time as first time anything won't go smoothly Good luck.

mcheung

[quote=mleskovar;4805001]Your symptom.....flapping noise (like a book closing? )...sounds like the linkage. Do both sides if you go in there.

Do you think the footwell linkage will cause the 1-2 minutes delay in air blowing through any vents? Even if you put the system to Auto or increase the fan to Max, it's just silence, nothing comes out anywhere, until a minute or two.

tarokyama

You guys can go the route I did, the cheapo route,

my drivers side foot vent stepper motor arm was broken, so I removed my
stereo (fairly easy) and used a screwdriver to unplug the actuator that was broken leading to the footwell. A word of advise. make sure the flap is CLOSED
before you decide to unplug the the actuator.... lol

mleskovar

Sounds like a problem associated with the blower motor. You can check if the motor shaft is free by going in through the cabin filter above the battery and moving the impeller by hand. It should spin freely. Wait for it to be cold/unused before you try it.

mcheung

Yes, the motor shaft spins freely. What else could cause no air to blow until 1-2 mins after you turn on the fan/AC? If it's the blower motor, where is it? Is that easy to change?

mleskovar

If the blower motor fan isn't operating it's either a bad fan, bound up, or not getting the correct data to turn on. I haven't had experience with a bad fan but I have read some posts about faulty motor control circuitry and that's on the fan module. $300? for fan and easy replace after taking out glove box.

mcheung

Thanks. Is taking out the glove box easy? Do I need to go through all the steps on Page 1 to take the glove box out? I may just fix the arm linkage first. That itself looks like it is going to take my whole weekend

mleskovar

There's a panel underneath the dash on the passenger side that will give you access to the motor. It's the same one you remove to get to the cabin filters. Just a couple of screws hold it in. Removing the glove box just makes it easier to see. It's been a couple of years since I dropped the lower dash(es) so my memory may be wrong.

mcheung

Thanks. I'll try to replace the linkage arm first to see if it will magically solve the blower delay problem.

mcheung

I got the linkage arms (203-830-00-33) for $30 from a local dealer in Toronto. They asked for almost $300 for a stepper motor (203-820-16-42), and there's no return since it's an electrical part. This seems outrageous. So I haven't got the stepper motor for the just-in-case situation. I can find the same item from ebay for about $100 including shipping.

I have some more questions.
- Is the stepper motor the same as flap actuator motor (all the M2/1 to M2/10) in the HVAC guide?
- If someone says actuator lever, would that be the same as the linkage arm?
- If there's a problem with the stepper motor, or blower motor, would it report a problem when you read the diagnostics output (e.g., from http://www.dealextreme.com/p/mb-cars...s-benz-16919)? Would something cheaper like this do the job (http://www.ebay.com/itm/Mercedes-Ben...em3cb70958ee)?
- I wonder if there's really a problem with a stepper motor, how would I find out? As I described before, besides the footwell vent problem on the passenger side, I also have the intermittent blower-delay problem...
- I have another unrelated problem that I need to fix... my signal stalk won't hold position for right turn signal (left turn is okay). I read instructions about how to replace the signal switch, I am just afraid the SRS light will come on afterward since I have to remove the SRS connections from the steering wheel temporarily. Would one of the readers above be able to clear the SRS signal?

Thanks,
Michael

mleskovar

$300 is a rip off. I seem to remember the going price at parts stores on the internet being about $100 five years ago.


Yes

Yes

If you run the on board diagnostics to synchronize the stepper motors it will never stop. That could mean either the motor or the linkage but either way you go through the same process to replace either. You can also tell by the sound they make (if any) The linkage makes a ticking sound and the motor makes a louder snapping sound (as the internal clutch slips). I don't know if any of the diag packages pinpoint stepper motors or blower motor/regulator but I'm guessing they would.

barnesC240

I have the exact same problem with my 01 C240 and there isn't really anything you can do yourself there are 2 motor for the AC. My guy said if it was the "easy" one to get to it would be $400 if it was the other motor the entire dash has to be removed and that would run $1000+

mcheung

I didn't remember whether it was a tick or a snap. It was just annoying. It made the noise for about 2 weeks, then it stopped.

mleskovar

I'm guessing it was an actuator arm/linkage that finally fell completely in pieces. They usually first crack along the hexagon hole in the arm that the stepper motor shaft goes into. The ticking you hear is the shaft slipping inside the hole and when the piece breaks off the noise stops. The noise usually doesn't stop when the motor goes. Also if the ticking is always after startup, about every second, about 10 -12 times, then stops, it's the arm because that's when the footwell flaps cycle.

M5CLK

Kinda an odd question... My '02 C32 started making the loud ticking noise couple days ago and after trying all the venting directions, I'm pretty sure it's the left footwell vent which is the M2/10 that's stuck open? Since I'm in Hong Kong and my car is right hand drive, do you think I can get away without taking apart the dashboard bottom panel to access the M2/10? In fact, from the pictures I've seen here, would it be possible to access the M2/10 by just removing the COMAND housing without taking apart the panel between the radio and the glove compartment?

mleskovar

No.

M5CLK

I went ahead and try fixing the M2/10, I was lucky that I can access it without taking the COMAND cage apart (RHD), I managed to get to it by removing the shifter and center console and then the panel between the radio and glove box only. The arm was indeed broken and after replacing it, I did a resync but am still hearing the loud snapping noise, but then the test did pass... I tried all blower directions and couldn't find anything wrong. The nosie sounded as though it's either M2/7 or M2/9 so I took the glove box under panel down (Appearently, the charcoal filter and the blower motor is located in the passenger side on RHD) The snapping sound felt like it's coming from A32m1, but that wouldn't make sense since I'm getting a/c fine... If the A32m1 blower motor goes, I shouldn't get any air from the vents correct? Now my question is, how difficult or if it's even possible to remove the charcoal filter housing? Has anyone one done it to acess M2/7 or the rest of the motors? Thx!

mleskovar

It's hard to tell which motor/linkage is causing the noise because they are all mounted on the HVAC box and the noise/vibrations are transmitted throughout. One isolation method is to disconnect the ribbon cable from the stepper motors one at a time to take each out of the system. It won't pass the synch test but you won't get the noise when the right one is off. The loud snapping noise is the stepper motor clutch slipping. I had a hard time figuring out where the noise came from as well and it turned out to be the passenger window defrost vent.....I could just get to the ribbon cable to pull it....and left it that way because it requires the upper dash to come off!!

Onericali

For anyone trying to get to the one right behind the bar.

gap58

I have the same problem I believe. In January 2011, I was told I needed the footwell flap motor replaced for ONLY $900.00 for my 2004 320C. However in December 2010 my motor mounts collasped. Had them replaced and had reset ring gear adaptation, torque struts replaced, and new thrust arm link bushings to the tune of $900.00. Why wasn't the footwell flap motor be identified as needing to be replaced when this work was performed?

harrison1277

i have had a similar problem for about a year and a half, I have an 05 230k sedan, i get a little tweeting/ clicking noise when my AC is on settings between 1-3 but when i put it any higher the noise subsides.. any ideas?