A/C Help: Intermittent Fan, No Control, and Turns on when car is off
#1
Member
Thread Starter
A/C Help: Intermittent Fan, No Control, and Turns on when car is off
Hi All,
The other day I was running around with the A/C on “0” listening for a sound on the outside of the car - I didn’t turn it back on that night, and when I came back the next morning, the A/C fan would start (climate control non-responsive to change - all lights, etc, work, but does not control the on/off of the fan) and stop within 10 seconds, then “act” like it was going to turn on again.
I’ve disconnected the battery, tried to reset the system by holding the defogger/recirc buttons (LEDs kept flashing), and going into diagnostics mode on the control unit itself - I can go grab the codes if needed, but nothing seemed “off”.
Anyone had a similar problem? I’ve been looking for 2 days and haven’t found a situation quite like mine. I heard these cars let you know when they need Freon, but haven’t done this yet.
Thanks!
The other day I was running around with the A/C on “0” listening for a sound on the outside of the car - I didn’t turn it back on that night, and when I came back the next morning, the A/C fan would start (climate control non-responsive to change - all lights, etc, work, but does not control the on/off of the fan) and stop within 10 seconds, then “act” like it was going to turn on again.
I’ve disconnected the battery, tried to reset the system by holding the defogger/recirc buttons (LEDs kept flashing), and going into diagnostics mode on the control unit itself - I can go grab the codes if needed, but nothing seemed “off”.
Anyone had a similar problem? I’ve been looking for 2 days and haven’t found a situation quite like mine. I heard these cars let you know when they need Freon, but haven’t done this yet.
Thanks!
#2
Out Of Control!!
There are no self AC diagnostics on your car except when you ask for cooling and you get warm air you most likely have a leak and need freon. Take the car to an AC specialist who will put a set of gages on the car and provide a course of action.
#3
Member
Thread Starter
Here is a list of the diagnostic codes that you can pull from the actual climate command unit - I heard they could be pretty useful if you know what you’re looking for - I’ll try and hunt down a video of how to access the screen:
https://mbworld.org/forums/mercedes-...e-control.html
Edit - here’s the video:
#4
Member
Thread Starter
Wanted to bump this - car refrigerant systems are cold to the touch - fan blower not responding to the climate control module.
The previous owner I found out had a problem with the fan relay, which was replaced, but I found while I was under the passenger side dashboard that the blower was dangling by two screws, so I unplugged and remounted the fan hoping it would help something!
Any ideas?
The previous owner I found out had a problem with the fan relay, which was replaced, but I found while I was under the passenger side dashboard that the blower was dangling by two screws, so I unplugged and remounted the fan hoping it would help something!
Any ideas?
#5
Member
Thread Starter
ASLO: A new development
Today, I was driving over to the parts store to pick up some Freon, and when I had turned the car on, the climate control said “MAX AUTO COOL” or “AUTO MAX COOL” (I don’t remember specifically at the moment) and the engine fan was on - sounded like a jet engine. I was able to disengage it by turning down the “fan” on my climate control.
At first I thought it was because the car was hot, but while troubleshooting later in the night, it was only at 2-3 bars when I started it and the engine fan came on again.
I’m thinking of unplugging the fuse to the climate control/blower motor fuse to see if it resets anything next.
Looking for anyone whos had had similar problems - I know that there have been people, but maybe I’m not entering the right strings for search queries.
Today, I was driving over to the parts store to pick up some Freon, and when I had turned the car on, the climate control said “MAX AUTO COOL” or “AUTO MAX COOL” (I don’t remember specifically at the moment) and the engine fan was on - sounded like a jet engine. I was able to disengage it by turning down the “fan” on my climate control.
At first I thought it was because the car was hot, but while troubleshooting later in the night, it was only at 2-3 bars when I started it and the engine fan came on again.
I’m thinking of unplugging the fuse to the climate control/blower motor fuse to see if it resets anything next.
Looking for anyone whos had had similar problems - I know that there have been people, but maybe I’m not entering the right strings for search queries.
#6
Member
Thread Starter
Bumped. Still haven’t fixed this, and it’s getting warmer by the day. I’d also like to see which models had the same blower motors/regulators - I’ll be going up to the salvage this weekend to pull some parts. No CLKs, but plenty of E classes and C classes.
#7
Super Member
You can get all kinds of info from the codes done during an AC diagnosis...do some searches on this forum and others...here is a good starting point.
https://mbworld.org/forums/clk-class...-problems.html
https://mbworld.org/forums/clk-class...-problems.html
Trending Topics
#8
Newbie
Can anyone confirm this? And is there a DIY for R&R of the blower motor resistor for the W209? Also, are there A/C diags than can be pulled from the head unit?
Thanks
//BKU
2007 CLK63 AMG "Maxine" 1998 E430 "Gay"
#9
Member
Thread Starter
Bullrich, thanks for bumping this! Luckily it’s been really nice outside for the past month or so and the windows are always down anyway, but I haven’t completely fixed the issue yet.
After ordering the part you’ve listed above and installing, as soon as I plugged the fan in, it started blowing at full speed, even with the controller set to “0”. It’s also worth noting that the part had been changed before, and when looking at the fuse box on the drivers side, the fuse for the blower motor (I’m not sure what number at the moment) had sometime previously gotten so hot that the plastic housing melted around it. I believe this is from when the previous owner had an issue with the blower motor not going off - the part was changed and was working fine when I got it.
One additional note that the part I bought which replaced the blower regulator was a cheap one, so I’m going to do the same with a different part.
After ordering the part you’ve listed above and installing, as soon as I plugged the fan in, it started blowing at full speed, even with the controller set to “0”. It’s also worth noting that the part had been changed before, and when looking at the fuse box on the drivers side, the fuse for the blower motor (I’m not sure what number at the moment) had sometime previously gotten so hot that the plastic housing melted around it. I believe this is from when the previous owner had an issue with the blower motor not going off - the part was changed and was working fine when I got it.
One additional note that the part I bought which replaced the blower regulator was a cheap one, so I’m going to do the same with a different part.
#10
Newbie
Bullrich, thanks for bumping this! Luckily it’s been really nice outside for the past month or so and the windows are always down anyway, but I haven’t completely fixed the issue yet.
After ordering the part you’ve listed above and installing, as soon as I plugged the fan in, it started blowing at full speed, even with the controller set to “0”. It’s also worth noting that the part had been changed before, and when looking at the fuse box on the drivers side, the fuse for the blower motor (I’m not sure what number at the moment) had sometime previously gotten so hot that the plastic housing melted around it. I believe this is from when the previous owner had an issue with the blower motor not going off - the part was changed and was working fine when I got it.
One additional note that the part I bought which replaced the blower regulator was a cheap one, so I’m going to do the same with a different part.
After ordering the part you’ve listed above and installing, as soon as I plugged the fan in, it started blowing at full speed, even with the controller set to “0”. It’s also worth noting that the part had been changed before, and when looking at the fuse box on the drivers side, the fuse for the blower motor (I’m not sure what number at the moment) had sometime previously gotten so hot that the plastic housing melted around it. I believe this is from when the previous owner had an issue with the blower motor not going off - the part was changed and was working fine when I got it.
One additional note that the part I bought which replaced the blower regulator was a cheap one, so I’m going to do the same with a different part.
//BKU
#11
Member
Thread Starter
As for taking out the glovebox, I wouldn’t know as the passenger side kickguard (I’m not sure what the official name is for this) was already out when I got the car. Luckily, I don’t think taking out the glovebox is necessary. After you get the footwell protector out, you’ll see the blower motor. There are 4-5 torx screws that hold the motor in, and you’ll see where the wiring harness plugs into the regulator, nearest the firewall. I’d go ahead and unplug it first, and then prepare for putting yourself in some pretty awkward positioning. You’ll have to have your top half in the passenger side footwell and the lower half of your body out of the door.
Once you get the mounting screws out, and the blower motor is unplugged, it just drops down, which is why sometimes you need to get both hands in there. After that you’ll note that the regulator has two torx screws on it, and after you get it out, the actual fan will be in the way of the regulator coming out. You’ll have to unscrew the fan motor from the mounting apparatus. Once you get that out (two Phillips head screws), it’s swap, plug, and (in my case not so much) play.
I’ll look forward to hearing if this helps your problem. I’m really hoping my Climate Control module is still good, as it sounds like I have a stepper motor issue as well (clicks of doom!) and the left footwell flap is stuck open which I know from a STAR DAS run through.
Last edited by 04CLK5.4; 04-28-2018 at 04:48 PM.
#12
Newbie
BTW, I'm in the 214. Are you in the 512? I may actually be there next week for work.
#13
Member
Thread Starter
#15
Member
Thread Starter
Bullrich, thanks for bumping this! Luckily it’s been really nice outside for the past month or so and the windows are always down anyway, but I haven’t completely fixed the issue yet.
After ordering the part you’ve listed above and installing, as soon as I plugged the fan in, it started blowing at full speed, even with the controller set to “0”. It’s also worth noting that the part had been changed before, and when looking at the fuse box on the drivers side, the fuse for the blower motor (I’m not sure what number at the moment) had sometime previously gotten so hot that the plastic housing melted around it. I believe this is from when the previous owner had an issue with the blower motor not going off - the part was changed and was working fine when I got it.
One additional note that the part I bought which replaced the blower regulator was a cheap one, so I’m going to do the same with a different part.
After ordering the part you’ve listed above and installing, as soon as I plugged the fan in, it started blowing at full speed, even with the controller set to “0”. It’s also worth noting that the part had been changed before, and when looking at the fuse box on the drivers side, the fuse for the blower motor (I’m not sure what number at the moment) had sometime previously gotten so hot that the plastic housing melted around it. I believe this is from when the previous owner had an issue with the blower motor not going off - the part was changed and was working fine when I got it.
One additional note that the part I bought which replaced the blower regulator was a cheap one, so I’m going to do the same with a different part.
Heres a picture:
Last edited by 04CLK5.4; 06-09-2018 at 04:47 PM.