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I'm a newbie to this forum, Ive only recently bought my My ML270cdi ('01) 64k and its having the same problem as the above posts, basically Air Con wasnt working, had it checked by a local MB independent, who put it on STAR and found a leak on Condenser, cost to replace £700+ (£230 for condenser, rest labout and VAT). Sod that for a game of soldiers, spent 2 weeks checking ebay, got a brand spanking new condenser in a damaged box for £40! plus postage, result #1!, got it fitted and regassed for £160, saved over £500 so as they say on the adver, £40 for parts, 160 to fit it, shopping around for a sensible mechanic... priceless!
A/C is freexing in engine bay upto firewall, but i havent got any control over it inside the cabin, if Iturn temp dial to minimum (blue) it still blows warm air, Whilst I cant hear a clicking from the blended air motor, there is noise from a flap beneath the windscreen vent. it cycles but sounds very tight and laboured, I also have the urge to check the blended air motor and linkage. my ML is a R/H drive model, all the posted fixes seem to be for L/H drive variants so will the motor be on MY drivers side or passenger side of the dash. Ive had the radio and centre section out, couldnt see it, had the instrument cluster out today, still couldnt see it, any help/suggestions would,be appreciated.
I discovered after battling with my ML trying to get access to the stepper motor a very easy solution! It is nearly impossible to find a way to unscrew the existing stepper motor which is located under the dashboard behind the glove box and passenger air bag. With the airbag and glove box removed, I found a flexible carburetor screwdriver at my local AutoZone that allowed me to unscrew the 2 phillips head screws mounting the stepper motor with ease. This screwdriver is about 10 inches long and completely flexible. I probably had a nearly 130 degree bend in it allowing me to easy access and mobility without having to take the airbag cover off of the dashboard! I am attaching a picture of the screwdriver so that you can see what it is.
See the grille/vent in this picture below the Low Range Switch??
Well, there a NTC resistor (sensor) behind this grille below the low range switch senses the in-cabin temperature. A white hose (about 5/8" diameter) connects it to the main climate box thus drawing air across the sensor. This sensor is directly behind this grille (if you look carefully thru the grille in this picture, you can sor-of make it out) Anyway, the air temperature is controlled by a variable resistor rotary control. Signals from the resistor to the amplifier determine the desired interior temperature output of the system. A switch at detent position at the full counter clockwise (maximum cooling) position overrides the air recirculation switch to close the fresh air door for maximum interior cooling (with A/C on). I'm not kidding, by dumb luck, all I did was to push the hose back on and my Blend Air started working as advertised!!
To access this hose, follow the instructions for pulling the radio in this thread. Once the radio is out, it is easy to push the hose back in place behind the sensor.
BTW, hats off to all posters on this site...you guys/gals have saved me a butt-ton of $$$!
I had air temp issues were I always had warm (not hot) air in the cabin when the air conditioner was switched off. I checked movement etc of the air/blend motor and could not find any fault. In any case when I checked the temp sensor I found that there was no white hose connected. I quickly found it and reconnected the open end to the sensor as mentioned by slugward. I added a cable tie as the connetion was fairly loose so hopefully that should keep it in place for a long while. PS this issue has been occurring for nearly six months now. So now it is all sorted out. A quick simple easy fix problem.
I'm a newbie to this forum, Ive only recently bought my My ML270cdi ('01) 64k and its having the same problem as the above posts, basically Air Con wasnt working, had it checked by a local MB independent, who put it on STAR and found a leak on Condenser, cost to replace £700+ (£230 for condenser, rest labout and VAT). Sod that for a game of soldiers, spent 2 weeks checking ebay, got a brand spanking new condenser in a damaged box for £40! plus postage, result #1!, got it fitted and regassed for £160, saved over £500 so as they say on the adver, £40 for parts, 160 to fit it, shopping around for a sensible mechanic... priceless!
A/C is freexing in engine bay upto firewall, but i havent got any control over it inside the cabin, if Iturn temp dial to minimum (blue) it still blows warm air, Whilst I cant hear a clicking from the blended air motor, there is noise from a flap beneath the windscreen vent. it cycles but sounds very tight and laboured, I also have the urge to check the blended air motor and linkage. my ML is a R/H drive model, all the posted fixes seem to be for L/H drive variants so will the motor be on MY drivers side or passenger side of the dash. Ive had the radio and centre section out, couldnt see it, had the instrument cluster out today, still couldnt see it, any help/suggestions would,be appreciated.
Hi Bruno27
Did you get any infor regarding where the air/blend motor is positioned on the RHS ML320? I also have a Right hand side model and need to replace my air/blend motor.
to be honest i never bothered fixing it in the end. ive worked out a procedure to force it to work and just stick with that. Ripping the dash out sounds like a nightmare and I simply couldnt be arsed. i dismantled as much of the dash, dials, glove box and radio/heater as i could get out and there are about 7 IDENTICAL actuator motors and i could fathom out which was which. I can have heat when its cold by turning temp selector towards full but still cant lower temp unless i turn the temp selector to minimum and turn the iginition off. when i turn the iginition back on i get ice cold air, but move the temp dail and its back up to full, it also goes full tilt if i leave the temp on minimum and turn the fan up over speed 2. its a bit of a pain but will have to do until i get rid of the old bus
Did you get any infor regarding where the air/blend motor is positioned on the RHS ML320? I also have a Right hand side model and need to replace my air/blend motor.
Appreciate any help that you can give.
ive looked at a couple of photos posted earlier in this thread and there is an actuator motor in the very place pictured. at the time I wasnt sure if it was the motor i was after but it seems that it was, i was able to reach that one by removing the glove box ( UK passenger side) and could get my hand on it at a push and was able to grease it (i greased all the motors i could reach at the time) i didnt have to remove the airbag or air bag cover, as for removing it i couldnt get to all 3 screws with my dumpy phillips screwdriver but managed to remove 2 before admitting defeat and putting them back in. you might have more luck than me
Hello Benny, thanks for the link. The parts link show the pins though as 2 pin, then space, then 3 pin from left to right. On my 98 ML320 the pins are 3 pin, space, then 2 pin. Are you saying the part you linked will also work or did you mean to link another part that had the correct pin placement?
Your problem might be with blend door actuator motor. It is located on top of the A/C system (behind the radio) and regulates the temperature of the airflow. You can do a check and/or repair after removing the instrument panel. Good luck!
Hi tirkes i have this exact same problem on my 2001 C240 is the lever on the same spot or where can i locate it if you know thanks for your help in advance!
I have this problem on my car its a 2001 c240 (w203) my heater won't work it just trows of cold air they told me to replace the blend door actuator but i don't know where it's located and how to access it if anyone can help me out i really do appreciate it thanks!
I have this problem on my car its a 2001 c240 (w203) my heater won't work it just trows of cold air they told me to replace the blend door actuator but i don't know where it's located and how to access it if anyone can help me out i really do appreciate it thanks!
Brian you are on the wrong forum. Here are the instructions for removing and installing the Blend Door Actuator, but in the future you must direct all further questions on the correct forum.
I seem to have a similar problem to those listed here. Recently acquired an old ML320 1998 there is an occasional, but annoying clicking from the air control switch. You can stop noise by dialling more heat from cold and it will stop. Then other days it all works perfectly but then click is back. Is it likely that mine is a similar problem to those listed? Any help appreciated thanks.
Hello Benny, thanks for the link. The parts link show the pins though as 2 pin, then space, then 3 pin from left to right. On my 98 ML320 the pins are 3 pin, space, then 2 pin. Are you saying the part you linked will also work or did you mean to link another part that had the correct pin placement?
Using the AC Delco part you need to unscrew the case and take the gearset out and place in the Mercedes case . The gearset is the part that strips . All else is the same and it will work perfectly .
Thank you it has confirmed my fears there was a faint hope someone would say that there was a leaf or something stuck in a vent!! Off now to strip it all down. Is there nay feedback from someone who used the inards from the AC Delco part mentioned and if it worked successfully.?
I have a 1999 ML320. I do not get hot air from the vents. Anti freeze mix and level is okay. I get air at floor, defrost, or or straight on when I adjust the setting so I believe the air damper blend door is functioning properly. Does this sound like a thermostat problem?
I have a 1999 ML320. I do not get hot air from the vents. Anti freeze mix and level is okay. I get air at floor, defrost, or or straight on when I adjust the setting so I believe the air damper blend door is functioning properly. Does this sound like a thermostat problem?
There are two possibilities causing your problem. The first is the Blend Door Motor and the other is the Amplifier/Relay N19.
You will have to conduct the below tests using a DVOM to narrow down the problem. To do so remove both covers under the instrument panel and at the left side remove the one Phillips screw holding N19 (small box the size of a pack of cigarettes). Then pull N19 out through the right side and conduct the tests.
03-28-2010, 05:04 PM
