Ben'sBenz

I've been looking around the forums for information regarding the sweaty sock smell that my car has when first turning on the AC. I found this info about enabling a low speed fan for 30 minutes after the car is turned off to assist in drying out the system.

https://mbworld.org/forums/3649173-post1.html

Thanks!

Ben'sBenz

bump...

Glyn M Ruck

Running the system on hot prior to shutdown will also prevent bacterial growth on the evapourator. But you need to kill the stuff.

https://mbworld.org/forums/attachmen...y-a_c-odor.pdf

Ben'sBenz

Thanks for your response Glen. I took the car to the dealership and they said MB no longer covers this under warranty. Do you know how i can go about checking the drain for the condensation? I have Never had any water dripping under the car while the AC was running. Regards,
Ben

Ben'sBenz

What I meant was checking the drain for a clog....

aowhaus

You should try Einszett Klima-Cleaner.
It's an air conditioner treatment spray that disenfects the musty/mouldy smell inside your air vents. It's an aerosol spray with a tube attachment which you stick into the vents.
Like all of Einszett's cleaning products I've used, it works very well.

Glyn M Ruck

No water dripping. Wow - I'm surprised you don't have wet carpets. This is a W203 diagram but the W204 is just a minor modification of this housing.

See drain tube at the base of the housing. You need to get the car on a hoist & locate where the rubber tube goes through the tunnel & clear it of obstruction.

Your dealer is full of BS BTW.

IGB

Agreed... (Can't say I hear it every day so...) Not a week goes by without having someone walk up to me with that "I'm so sorry" look to tell me that my car is leaking water.

Sportstick

Instead of trying to outguess the system by running it manually just to keep it dry, simply place it in AUTO. There is good, albeit anecdotal, evidence that the car's HVAC system has been designed to take care of itself. Mine has been in AUTO for 4 years with no smell. I only vary the temperature set to accommodate passenger comfort, and on rare occasion have used MAX COOL, but then soon returned it to AUTO. Works perfectly, and, again, never a bad smell problem.

Ben'sBenz

Agreed Sportstick, however I use AUTO mode exclusively and it still smells awful. Thanks for the diagram Glyn. Do you know whereabouts the drain would be exposed under the car? I'm guessing forward of the passenger footwell somewhere? Also, does anyone have the latest WIS on the cleaning process? I want to see something that says the cleaning process isn't covered under warranty.

Sportstick

Interesting....did you buy the car new and use it that way since delivery? Yours would be the first one I've read about which was always in AUTO and still developed the smell. If so, this probably increases the likelihood of the blockage diagnosis.

Ben'sBenz

No, I bought it 13K miles used. Is it possible that the condensation is dripping on top of that plastic splash shield causing me not to see water runoff?

Glyn M Ruck

You need to remove the bottom cover. The drains are either side of the transmission at the bulkhead/firewall.

If you pull back the carpets you should see them going through the tunnel.

I have no WIS doc.

Andr3an

Saw this and went to the dealer to get it fixed since the warranty expires in couple weeks. I was told that mercedes benz no longer covers this under the warranty.
I even showed the guy the TBS and he told me it is outdated (2009) and they have new orders from MB saying to just replace the charcoal filter located under the passenger's side dasboard. It costs $97 installed.

I even asked to see the new TBS and he said he couldnt let me take a look at it.

B.S.?

RENNTECH

it is not B.S. the evap foam cleaning procedure is not covered under mb warranty.

This bulletin has been created and maintained in accordance with MBUSA-SLP S423QH001, Document and Data Control, and
MBUSA-SLP S424HH001, Control of Quality Records.
© 2009 Mercedes-Benz USA, LLC. All rights reserved. Reproduction or translation in whole
Mercedes-Benz Canada, Inc. or in part is not permitted without authorization from the
Dealer Workshop Services publisher. Printed in U.S.A.
www.MBUSA.com 1-800-FOR-MERCedes
www.startekinfo.com
Date: October 20, 2011
Order No.: S-B-83.30/134a
Supersedes: S-B-83.30/134, August 18, 2011Group: 83
Revision a: Note added for models equipped with recirculated air filtering and biocide-coated
evaporator.
SUBJECT: MY-All, Models 164, 171, 203, 209, 211, 215, 216, 219, 220, 221, 230 and 251
Air Conditioning Musty/Moldy Odor Complaints Cleaning Procedure
Under certain environmental conditions, typically in a hot and humid climate, the vehicle may emit a
musty/moldy odor from the air conditioning system. This may be more noticeable when starting the vehicle
due to residual condensation on the evaporator and on the interior surface of the heater box.
Note: For the following model series 204, 172, 166, 212, 207, 218, 164 as of A407859, 251 as of
A083326, 216 as of A012332, 221 as of A174161, equipped with recirculated air filtering and biocidecoated
evaporator.
In these vehicle models the evaporator can be ruled out as the cause of the odor. Cleaning the evaporator
is not an appropriate remedial measure. Therefore MBUSA does not recognize the cleaning of the
evaporator under warranty. The procedure if completed on these models can only be billed as customer
pay.
For additional information related to odor from the air conditioning system, also refer to:
• LI83.00-P-051588 in Xentry TIPS
• Diagnosis tree "Odor" from the Technology Guide "Vehicle Climate Control - Troubleshooting -
Function - Design - Operation". (The "Technology Guide - Vehicle Climate Control -
Troubleshooting - Function - Design - Operation" is available in pdf format in SDmedia SDS).
This bulletin describes the air conditioning evaporator and interior cleaning procedure for musty/moldy odor
using Mercedes-Benz Contra Sept and the A.C system “ultrasonic atomizer”. Refer to WIS document
AR83.30-P-5556A for information. For the best lasting results, follow the instructions provided below.
1. Remove all filters installed in the air conditioning system. The following filter may be fitted: Pollen
filter, dust filer, combination filter or active charcoal filter. Filters are not warrantable items and are
to be replaced as per maintenance recommendations and requirements.
2 S-B-83.30/134a
2. Clean evaporator with Mercedes–Benz Contra Sept as per WIS document AR83.30-P-5555T.
Contra Sept is applied using a spray gun attached to a long probe. It is imperative to have as much
of the evaporator sprayed with the cleaner by moving the probe in / out and up / down inside the
case. It may be necessary to bend the probe in order to gain access. The cleaner is applied and
allowed to dry. Refer to Figure 1a for spraying angle recommendation.
Note: After cleaning the evaporator, a second treatment has to be conducted. After completion of
section A (ContraSept), refer to section B (Wynns).
A. ContraSept Cleaning Procedure:
Caution! Wear safety glasses and respiratory protection when spraying cleaner.
Figure 1a. P-B-83.30/74k
• Spray the evaporator at a 90° angle.
• Move up and down, left and right to reach all
areas of the evaporator.
• Do not rotate the probe to reach other areas of
the evaporator. This will change the spraying
angle and the cleaning effect will diminish.
Warning! Do not exceed the manufacturer’s recommended maximum air pressure as stated on the
label affixed to the pressure cup (Figure 1b). Excessive air pressure could cause the canister to explode
and potentially cause personal injury. The recommended pressure to clean the evaporator effectively is
120psi.
Figure 1b. P-B-83.30/74g
To reduce the possibility of this condition reoccurring, advise the owner to operate the blower at a higher
speed, especially during humid conditions. For vehicles with a REST function, it also helps to use this
feature during humid conditions when parking the car.
Additional Procedures – Model 203 / 209
1. Equipped with ACC climate system Option Code 580 - It is necessary to drill a 15mm hole in the
climate housing to access the evaporator with the spray probe. The location for drilling the hole is
described in WIS document AR83.30-P-5555-01A and Figure 1, A1 and B1.
S-B-83.30/134a 3
2. A white foam block may be mounted to the housing between the blower motor and the main section
of the case, see (Figure 2). On these housings, there is an alternate location of the hole as shown
in Figure 1, A2 and B2.
Figure 1. P-B-83.30/74h
Without foam block as in WIS AR83.30-P-5555-01A
Dimension A1 = 30 mm
Dimension B1 = 25 mm
With foam block
Dimension A2 = 10 mm
Dimension B2 = 15 mm
Figure 2. P-B-83.30/74h
3. Bend the shorter of the two probes (Figure 3). Move the probe up and down as well as side to side
to ensure the entire evaporator is sprayed with the cleaner. Plug hole after cleaning with seal plug
A110 987 10 44 64.
4. Using the instructions below check the ‘REHEAT' setting. It should be set to ‘Anti-icing’.
Control Units �� Body �� EIS �� Control unit adaptations �� Read coding and change if necessary
�� Climate control �� Standard setting: Climate control �� REHEAT mode �� Change From:
“Standard” to: “Anti-icing protection”
5. Should a customer report on the air conditioning system emitting a musty/moldy odor from the
vents within three months after using the Mercedes-Benz Contra Sept product as described above,
a Biocide coated evaporator can be installed on 203 vehicles (production up to VIN A731367 and
F634899) and on 209 vehicles (production up VIN F144090 and T042953). The Biocide coated
evaporators were phased into production on these vehicles past the VINs indicated above. Be sure
to thoroughly clean the inside of the heater box and make sure the drain tubes are not clogged
before reassembling the system.
4 S-B-83.30/134a
Figure 3. – Bend probe as shown P-B-83.30/74k
Additional Procedures – Model 211
1. Using the instructions below, check the ‘REHEAT' setting. It should be set to ‘Fixed value’.
Control Units �� Air Conditioning �� C-AAC, AAC �� Control unit adaptations �� Read coding
and change if necessary �� Workshop coding �� Evaporator-Control (REHEAT mode) �� Change
From “Humidity–dependent (SERIES)” To: “Fixed value”
2. In case of customer reports that the air conditioning system is emitting a musty/moldy odor from the
vents within three months after using the Mercedes-Benz Contra Sept product as described above,
a new slanted heater box bottom which allows the condensation to drain better and a coated
evaporator entered production as of VIN A675828 and X171590. In this case, these parts can be
installed in earlier vehicles. Be sure to thoroughly clean the inside of the heater box and make sure
the drain tubes are not clogged before reassembling the system.
Procedure for 164 and 251
Caution! Wear safety glasses and respiratory protection when drilling hole and spraying cleaner.
1. Clean the evaporator with Mercedes–Benz Contra Sept as per WIS document AR83.30-P-5555T
and the additional information in this document.
2. To clean the driver side of the evaporator, the spray probe is inserted into the hole for the
evaporator temperature sensor as described in WIS document AR83.30-P-5555T, Step 4.1.
3. To clean the passenger side of the evaporator, the spray probe is inserted into a 15 mm hole that
needs to be drilled in the climate housing as described in Steps 4 through 6.
4. Remove the cover below the instrument panel on the passenger side and fold carpet down. Refer
to WIS document AR68.10-P-1520GZ (164) or AR68.10-P-1520RT (251).
5. Location of hole is shown in Figures 4 and 5. The hole should be centered in the triangular shaped
section of the climate housing as shown in Figure 5.
6. Drill a 15mm hole in small increments using a mechanical drill stop to limit how far the drill bit
penetrates the climate housing. A collar type drill stop, a piece of rubber hose or tape can be used
as the drill stop.
Warning! The drill bit cannot be allowed to penetrate the housing more than 13mm or damage to the
evaporator could occur. When the drill bit breaks through the housing it has a tendency to pull inward.
This is why a drill stop is necessary.
Figure 4. S-B-83.30/74k Figure 5. S-B-83.30/74k
7 Bending of the probe may be required to be able to spray all parts of the evaporator. Move the
probe up and down as well as side to side to ensure the entire evaporator is sprayed with the
cleaner.
8 Follow the remainder of instructions in WIS document AR83.30-P-5555T. Reassemble vehicle in
reverse order. Do not replace any filter back into the system!
S-B-83.30/134a 5
Warning! Do not exceed the manufacturer’s recommended maximum air pressure stated on the
label affixed to the pressure cup (Figure 3). Excessive air pressure could cause the canister to explode
and potentially cause personal injury.
B. Wynns Treatment
1. Warm up vehicle with air conditioning switched off for a minimum of 30 minutes in order to dry out
the climate housing and ducts. Set the climate control to the following settings:
Blower speed 2-3
Heat to maximum
Recirculation activated
Air distribution to the footwell
All doors, windows and sliding roof closed
Note: AC compressor does not turn off immediately when the AC Off is selected at the control
module. In order to ensure the compressor is off, use the following instructions:
Select AC Off
Select Climate System Off
Select Climate System On. The AC compressor will now be off.
2. Remove all filters installed in the climate system. This could include dust, activated charcoal or
combination filters.
3. Close the recirculation flap for cleaning using SDS.
For 171, 211, 219, 216, 221, 164 and 251 models follow path: Control Units �� Air
Conditioning �� C-AAC, AAC �� Actuations �� Closing air recirculation flap for cleaning �� Select
recirculation.
For 203 and 209 models, follow path: Functions performed by more than one control unit ��
Body �� Climate control �� Climate control �� C-AAC �� Actuations
The system will come out of recirculation when SDS is disconnected from the vehicle.
Note: This menu item is not available in SDS for all vehicles. On these vehicles, recirculation must be
manually selected on the control module.
4. Place the Wynn’s® AIRCOMATIC™ Ultrasonic Cleaning System in the passenger footwell. Insert
the hose in the luggage net and orient the end of the hose to insure the output from the device is
sucked into the footwell vents.
5. Start engine, AC off, press recirculation button, select lowest blower speed and set the
temperature(s) to minimum.
Note: The compressor must not be running.
6. Install one container of Wynn’s® AIRCO-CLEAN™ in the Wynn’s system.
7. Plug in the Wynn’s system and check that it is running.
8. Close all doors and windows.
9. When the fog stops coming out of the Wynn’s® system (after approximately 20 minutes), the
dispersion process has been completed.
10. When the cleaning procedure is finished, switch engine off, turn off the Wynn’s® system and leave
windows and doors closed for approximately 1 hour.
11. Open doors and trunk lid/tailgate.
12. Open the air recirculation flap again if the automatic recirculation function has been deactivated by
coding, and set the recirculated air function to “unimited” again.
6 S-B-83.30/134a
13. Restart engine, switch on A/C, select the highest blower speed and set the temperature(s) to
minimum.
14. Allow system to run for about 10 minutes. The cleaning process is now complete.
15. After cleaning, install new filters.
To reduce the possibility for this condition to reoccur, advise the owner to operate the blower at a higher
speed, especially during humid conditions. For vehicles with a REST function, it also helps to use this
feature during humid conditions when parking the car.
Parts Information
Qty. Part Name Part Number
ContraSept treatment
1 Spray gun and probes A000 581 00 04
1 Mercedes-Benz Contra Sept (1 liter bottle per vehicle) A009 989 61 71
1 Spray probe, short A000 581 00 05 *
1 Spray probe, long A000 581 01 05 *
1 Mixer insert A000 997 15 03 *
1 Coupling A005 997 47 89 *
1 Flat sealing ring A016 997 91 45 *
1 Coated evaporator (211) A211 830 07 58
1 Heater box bottom A211 830 22 03
1 Biocide coated evaporator (203 and 209) A209 830 03 58
1 Seal plug for drilled hole A110 987 10 44 64
Wynns treatment – order through SSEP Catalog, Section E3
1 Ultrasonic atomizer 211 – 03000
1 Interior cleaner 211 – 30208 1
* Replacement parts for Spray gun, order only when needed
1 Part number is quantity of 12. Submit as local purchase WYNN03354, quantity of 1.

RENNTECH

Also in response to the evap dry feature, it has been causing many more problems than its solving especially in the 207. cars in regards to battery drain issues. it is the first feature we are turning off in the event of any battery concerns. evap cleaning along with changing the cabin filter at every service instead of just with the B is the best solution

Glyn M Ruck

Thanks for posting. Why I say BS is that Benz started microencapsulating the evaporator with biocide & it has not worked. In my opinion they should continue to cover this under warranty as they always used to per the bulletin I have previously posted.

RENNTECH

100% agree sir. Just wait until you guys get a whiff of whats going on with the new vehicle maintenance contracts. going to be an uproar .

niteryder

Old school trick is to turn the fan on high and spray Lysol into the outside fresh air vent. Recirculation should be off. Do that a few times and it should kill the bacteria and smell.

http://www.lysol.com/cleaning-produc...nfectant-spray