W212 2012 Heater/Interior Fan Does not Work
#1
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W212 2012 Heater/Interior Fan Does not Work
Hello, my fan for heating/ A/C /ventilation inside the car is down. None of 5 speeds is working,even though it shows 1-5 speeds on the display. The Heat and A/C are working, I feel it is coming out on the Highway, but not the fan. Any suggestions which fuse/relay shall I check first? I can not find a good map for fuses/relays anywhere with clear indication of what is what.
MB E-350, W212, 2012. I would appreciate any help.
MB E-350, W212, 2012. I would appreciate any help.
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RWagz (07-29-2023)
#2
MBWorld Fanatic!
No idea on fuses but you should be able to find a fuse guide online or in your trunk with spare. There was a post a while back where someone replace their blower motor from below the dash (behind the glovebox) which does not appear to be working for you right now.
How do you know heat and AC are working? Have you removed the intake cowl to view the fan to check on it from above?
How do you know heat and AC are working? Have you removed the intake cowl to view the fan to check on it from above?
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egb (07-20-2019)
#3
Newbie
Thread Starter
Blower motor I think is to far yet, I have to start from Fuses/relays. Heater/A/C are working. As I mentioned, on the Highway heat and cold air are cumming out. And I do not hear a fan sound any more switching speeds. No air flow coming out of fan grids when I am standing.
#4
MBWorld Fanatic!
Do what thefisch recommended and look at the fan behind the cabin filter. It may have something....like a dead mouse....impeding it or it just may be stuck and need a helping hand to get started. Then go look for blown fuses. No, I don't have a fuse map for your year but there's one some place. They hide it in different places and usually in one of the fuse boxes.
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#8
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OK, after trying to shame you into searching I went back to the link to copy it for you and at closer inspection it's for a C Class!! I found my fuse map in the trunk folded up in the tool kit. Here......
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RWagz (07-29-2023)
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#13
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#14
Well it’s freezing so gave into the dealer. 45 min in the waiting room. Payed 550$ and I’m set. DIY would have been great but time and convienance... pay to play!
thanks though! Hopefully it helps someone. We need to keep this forum strong with this type content!
thanks though! Hopefully it helps someone. We need to keep this forum strong with this type content!
#15
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#17
Working at the Moment
I had the same problem today, 1/13/2019. I actually tried to turn the fan blades with my hand, and met some resistance, but continued to give it a couple of turns to make sure it wasn't getting stuck. Started the car, turned the blower on, and how about that...it's working again. Not sure for how long though.
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RWagz (07-29-2023)
#18
I had the same problem today, 1/13/2019. I actually tried to turn the fan blades with my hand, and met some resistance, but continued to give it a couple of turns to make sure it wasn't getting stuck. Started the car, turned the blower on, and how about that...it's working again. Not sure for how long though.
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RWagz (07-29-2023)
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#20
Member
I had this exact same problem. Manually spinning the fan made it work again!
So is this a warning that tells me I should replace that fan before it stops working for good?
I'm getting two different parts for the blower mower resistor. Both are about as expensive as the blower motor itself. Rock auto shows two very different pictures:
I still have varying fan speeds so I'm going to leave that until it fails. Just to be sure - These are just resistors that "fail open" so any issues with this regulator won't harm the motor. I don't want to damage a new motor because I should have replaced this regulator. Thoughts?
So is this a warning that tells me I should replace that fan before it stops working for good?
I'm getting two different parts for the blower mower resistor. Both are about as expensive as the blower motor itself. Rock auto shows two very different pictures:
I still have varying fan speeds so I'm going to leave that until it fails. Just to be sure - These are just resistors that "fail open" so any issues with this regulator won't harm the motor. I don't want to damage a new motor because I should have replaced this regulator. Thoughts?
Last edited by RWagz; 07-29-2023 at 04:49 PM.
#21
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MY'14 W212 M276 3.5NA @60kMi
fan of ballast fan
These fans are purposely built tight and dry right from the Eastern europe BOSCH factory. They start squeaking at 10kMi.
I don't think the fancy ballast is involved in killing the fan. More like the fan overheats the ballast cooked without proper air flow (plugged cabin filter!!)
Here is the facelift ballast for ya...
Great unit in contrast with the defective fans.
cabin blower controller
heatsink area
I don't think the fancy ballast is involved in killing the fan. More like the fan overheats the ballast cooked without proper air flow (plugged cabin filter!!)
Here is the facelift ballast for ya...
Great unit in contrast with the defective fans.
cabin blower controller
heatsink area
Last edited by CaliBenzDriver; 07-29-2023 at 05:19 PM.
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CaliBenzDriver (07-31-2023)
#23
Any instructions?
Reply: where is the blower motor precisely?
Did you find any instructions on how to replace it that you can share with us?
Please?
Did you find any instructions on how to replace it that you can share with us?
Please?
#24
Member
Same issue in a Canadian 2013 GLK350. Removed the blower motor assembly, it was absolutely coated with carbon from the motor brushes. Flushed the motor well in rubbing alcohol (an incredible amount of black carbon sank to the bottom) allowed to dry completely and reinstalled. Worked great for a year. This fall, failed again, but due to the commutator being coated in brush carbon.
Removed it by gently holding a narrow screwdriver tip against the commutator while manually spinning the motor. Carefully used a knife point to ensure no shorts between the the commutator connections (the shiny copper bars of the commutator), then blew all the dust out. Yup, a pretty awful backyard mechanic repair - but it worked to save me quite a few dollars, plus I learned something.
Works great now, but I imagine I'll have to replace it next year.
Just remember if using flammable cleaners to ensure that the motor is COMPLETELY DRIED OF THE CLEANER before reinstalling the motor.
Removed it by gently holding a narrow screwdriver tip against the commutator while manually spinning the motor. Carefully used a knife point to ensure no shorts between the the commutator connections (the shiny copper bars of the commutator), then blew all the dust out. Yup, a pretty awful backyard mechanic repair - but it worked to save me quite a few dollars, plus I learned something.
Works great now, but I imagine I'll have to replace it next year.
Just remember if using flammable cleaners to ensure that the motor is COMPLETELY DRIED OF THE CLEANER before reinstalling the motor.
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CaliBenzDriver (12-02-2023)
#25
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2014 Mercedes-Benz E350
I had this exact same problem. Manually spinning the fan made it work again!
So is this a warning that tells me I should replace that fan before it stops working for good?
I'm getting two different parts for the blower mower resistor. Both are about as expensive as the blower motor itself. Rock auto shows two very different pictures:
I still have varying fan speeds so I'm going to leave that until it fails. Just to be sure - These are just resistors that "fail open" so any issues with this regulator won't harm the motor. I don't want to damage a new motor because I should have replaced this regulator. Thoughts?
So is this a warning that tells me I should replace that fan before it stops working for good?
I'm getting two different parts for the blower mower resistor. Both are about as expensive as the blower motor itself. Rock auto shows two very different pictures:
I still have varying fan speeds so I'm going to leave that until it fails. Just to be sure - These are just resistors that "fail open" so any issues with this regulator won't harm the motor. I don't want to damage a new motor because I should have replaced this regulator. Thoughts?
Most of the repairs I've done, the blower actually would blow as intended, but was pulling 5 to 10 amps too much for the resistor to live very long. For this reason I would replace both blower motor and resistor to ensure proper operation of system and amp draw.
As for which blower control, you need your build sheet with codes for your car, The top one in your picture is for cars with (code 800) for the climate control system.
But this is based on the work I've done using proper testing equipment, technical data, and schematics to guide me. Your mileage may vary.
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CaliBenzDriver (12-02-2023)