Burning electrical smell from AC vents
Thread Starter
Senior Member
Joined: Mar 2014
Posts: 339
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From: Nevada
2014 E63S, 2018 GLC 300
Burning electrical smell from AC vents
Once the car has been operated for over 20 minutes a strong electric burning/chemical smell comes from the AC vents. Anyone heard of a problem like this? I am trying to figure out where it comes from whether it is from the fan motor or picking it up from above the battery.
I did smell fumes coming from the battery, has this been a source of electric smells? Whoever thought picking up fresh air from the engine compartment is a good idea is crazy.
Ideas?
I did smell fumes coming from the battery, has this been a source of electric smells? Whoever thought picking up fresh air from the engine compartment is a good idea is crazy.
Ideas?
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Joined: Jan 2009
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From: Northern VA
W211
could be your voltage regulator going on the alternator, so in short time you may get the red battery code and/or convenience functions temp disabled. Get this checked before you are left stranded.
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Joined: Jun 2008
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From: San Diego
2012 CLS63 AMG Performace - Obsidian Black
Take off the 10MM plastic nut off of the filter compartment, and look at the secondary battery itself. Make sure you don't have any shorts or other nasty things going on with the battery wiring. If it was your VR on the alternator burning, you'd definitely have some other symptoms and interesting lights.
Check your fan motor as well- I had an FSS relay (fan speed) burn up my an old W210, and had an electrical smell as well. It only manifested itself after 20-30 minutes of driving with the A/C on. Good luck.
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Joined: May 2009
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From: Santa Clara, Ca
2003 SL55 / 2002 SLK32
I would take a look at your blower motor (fan) regulator ... this can make smoke come from the vents when it fails. It will also kill the blower motor itself.
Chris
Chris
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From: Caribbean/Florida/Colorado
E-ZGO 53hp., 1999 E 430 sport, 2004 E 55, 2008 Tahoe LTZ on 24"s
Well... Your fan shouldn't be sucking air from the engine compartment. The filtered intake over your secondary battery should be sealed from the engine compartment- Check the strip seal across the hood.
Take off the 10MM plastic nut off of the filter compartment, and look at the secondary battery itself. Make sure you don't have any shorts or other nasty things going on with the battery wiring. If it was your VR on the alternator burning, you'd definitely have some other symptoms and interesting lights.
Check your fan motor as well- I had an FSS relay (fan speed) burn up my an old W210, and had an electrical smell as well. It only manifested itself after 20-30 minutes of driving with the A/C on. Good luck.
Take off the 10MM plastic nut off of the filter compartment, and look at the secondary battery itself. Make sure you don't have any shorts or other nasty things going on with the battery wiring. If it was your VR on the alternator burning, you'd definitely have some other symptoms and interesting lights.
Check your fan motor as well- I had an FSS relay (fan speed) burn up my an old W210, and had an electrical smell as well. It only manifested itself after 20-30 minutes of driving with the A/C on. Good luck.
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Thread Starter
Senior Member
Joined: Mar 2014
Posts: 339
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From: Nevada
2014 E63S, 2018 GLC 300
Ok so yesterday morning I turned the fan on and no fan. Turned off and on but no fan. Turned back off then on and the fan has worked since yesterday. Any idea there?
Since then no funny smell. Weird.
Since then no funny smell. Weird.
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From: SF Bay Area, CA
2006 E55 and 2002 E320
Bring it in to the dealer.
At this point, since we haven't been able to figure it out, I urge you to bring the car into the dealer so it can be diagnosed before more damage is created. If you have a AAA membership with free towing, I'd tow it. Don't know if operating the car will make the problem worse or not.
Good luck!
At this point, since we haven't been able to figure it out, I urge you to bring the car into the dealer so it can be diagnosed before more damage is created. If you have a AAA membership with free towing, I'd tow it. Don't know if operating the car will make the problem worse or not.
Good luck!
