A/C System - Musty/Mildew Odors
Article No.02-11-7
06/10/02
AIR CONDITIONING - MUSTY AND MILDEW TYPE
ODORS - SERVICE PROCEDURE
FORD:
1994-1998 MUSTANG
1995-1998 CONTOUR, CROWN VICTORIA, ESCORT
1996-1998 TAURUS
1995-1998 WINDSTAR
1997-1998 EXPEDITION
LINCOLN:
1995-1998 CONTINENTAL, MARK VIII, TOWN CAR
1998 NAVIGATOR
MERCURY:
1995-1998 GRAND MARQUIS, MYSTIQUE, TRACER
1996-1998 SABLE
1995-1998 VILLAGER
Article 99-19-6 is being republished in its entirety to advise the use of Chemical Goggles.
ISSUE
Musty and mildew type odors may come from the air conditioning/beating system. These odors may be caused by mildew-type fungi growth in the A/C evaporator. It is most noticeable when the A/C is first turned on.
ACTION
A new Disodorizer(R) which encapsulates the mildew is now available to help reduce these odors. A new Moisture Purge Module (MPM) which operates the blower motor when the vehicle is parked to dry out the evaporator core is now available for these vehicles. Apply the Motorcraft A/C System Disodorizer(R) (YN-18 (U.S.) or CYN-18 (Canada) or equivalent meeting Ford specification WSS-M99B187-A) product to the A/C system, install the MPM as directed in the following Service Procedure, and review the Odor Service Tips.
WARNING
AVOID CONTACT WITH EYES AND SKIN. CONTACT WITH EYES AND SKIN WILL CAUSE IRRITATION WEAR CHEMICAL GOGGLES WHEN USING THE DISODORIZER(R).
WARNING
THIS PROCEDURE SHOULD ONLY BE PERFORMED IN WELL VENTILATED AREAS. OPEN ALL WINDOWS AND DOORS OF THE VEHICLE. LEAVE DOORS AND WINDOWS OPEN DURING THE ENTIRE PROCEDURE. AVOID BREATHING VAPORS.
WARNING
AVOID FLAMES, SPARKS OR LIT TOBACCO PRODUCTS. THIS PRODUCT IS COMBUSTIBLE.
WARNING
READ ALL INSTRUCTIONS AND WARNINGS PACKAGED WITH THE DISODORIZER(R). FOR ADDITIONAL INFORMATION, SEE THE MATERIAL SAFETY DATA SHEET (MSDA) FOR THIS PRODUCT.
SERVICE PROCEDURE
A/C ODOR TREATMENT PROCEDURE
NOTE
THIS PROCEDURE WILL NOT BE EFFECTIVE ON ODORS EMITTED FROM AREAS OTHER THAN THE EVAPORATOR CORE. FOR EXAMPLE: MILDEW ODORS DUE TO WET CARPET WHICH ARE RECIRCULATED BY THE A/C SYSTEM. BE SURE YOU HAVE IDENTIFIED THE TYPE AND SOURCE OF ODOR BEFORE PERFORMING THIS REPAIR.
Motorcraft A/C System Disodorizer(R) (YN-1.8 (U.S.) or CYN-18 (Canada)) is a full strength disodorizer which requires no dilution or mixing. Each vehicle treated will require 240 mL (8 fluid ounces) to complete the procedure.
NOTE
THE ROTUNDA A/C DISODORIZER(R) SPRAYER 164-R4700 IS ONLY TO BE USED WITH THE YN-18 (OR CYN-18) A/C SYSTEM DISODORIZER(R) AND SHOULD NOT BE USED FOR ANY OTHER PURPOSE.
The A/C System Disodorizer(R) can be applied using the Rotunda A/C Disodorizer(R) Sprayer 164-R4700. The disodorizer must be applied through the blower motor or the blower motor resistor/controller opening for proper coverage. Refer to the Disodorizer(R) Application Location Chart to determine which component to remove.
NOTE
SPRAYER MUST BE CHARGED COMPLETELY FOR PROPER ATOMIZATION OF THE DISODORIZER(R). FAILURE TO PROPERLY APPLY THE DISODORIZER(R) AS OUTLINED IN THIS TSB ARTICLE, WELL NOT ALLOW ALL OF THE MICROBIAL GROWTH TO BE CONTAINED AND WILL RESULT IN AN INCOMPLETE REPAIR.
1. Open vehicle windows.
2. Disconnect A/C cycling switch electrical connector.
3. Set the following:
^ A/C in vent or panel mode
^ Temperature at full heat Blower at high speed
^ Engine running at normal operating temperature
^ Vehicles equipped with a manually operated fresh air/recirculate air door, set the door to fresh air position
4. Run vehicle (Steps 1-3 conditions) for 15 minutes. This will dry out the system.
5.. Turn ignition off.
CAUTION
BLOWER MOTOR RESISTOR MAY BE VERY HOT.
6. Remove and disconnect lower motor or resistor/controller (refer to Disodorizer(R) Application Location Chart) by referring to the appropriate Service Manual, Section 12 or Workshop Manual, Section 412-02.
7. Insert the A/C Disodorizer(R) Sprayer (Rotunda 164-R4700) nozzle into the blower motor resistor/controller opening in the evaporator case and direct toward the face of the evaporator core. Spray the Disodorizer(R) until empty.
8. Wait 10 minutes before proceeding.
9. Reinstall and reconnect blower motor or resistor/controller.
10. Repeat Steps 1-5.
11. Reconnect A/C cycling switch.
12. Allow vehicle to sit for 30 minutes before returning to customer.
NOTE
REFER TO APPROPRIATE SERVICE WORKSHOP MANUAL FOR BLOWER MOTOR REMOVAL AND INSTALLATION OR RESISTOR REMOVAL AND INSTALLATION.
MOISTURE PURGE MODULE (MPM) INSTALLATION
1. Install the applicable MPM and wiring harness. Follow the procedure in the Instruction Sheet provided with the wiring harness.
2. Verify MPM operation.
ODOR SERVICE TIPS
Types Of Odors, Their Sources And Treatments
There are typically four (4) types of objectionable odors found in a vehicle, they are:
^ Chemical odors
^ Environmental odors
^ Microbiological odors
^ Human and other interior-generated odors
Odors can be described in a number of ways:
^ Musty
^ Mildew
^ Fishy
^ Sweet
^ Burning
^ Chemical
^ Fuel
^ Oil
^ Exhaust
^ Wet cement
^ Urine Tar
^ Fragrance
^ Body odor
Chemical odors:
^ Coolant: sweet smell
^ Fuel: gasoline or diesel fuel smell
^ Oil: oil type or burning smell
^ Power Steering Fluid: oil type or burning smell
^ Transmission Fluid: oil type or burning smell
^ Washer Fluid: alcohol type smell
^ Gear Lube: garlic/sulfur smell
^ Refrigerant/Oil: ether type smell
^ Carpet/Trim Adhesives: fishy, urine, or sweet smell
^ Evaporator Core Coating: wet cement type smell
Environmental odors:
^ Exhaust: exhaust, fuel, burning type smell
^ Industrial Pollutants: all types of smells
^ Dust: musty, mildew, wet cement type smell
^ Pollen: sweet smell
^ Tobacco: burning, tar smell
Microbiological odors:
Microbial growth supported by warm temperatures and moisture may occur on:
^ Foam Seals: musty, mildew smell
^ Rubber Seals: musty, mildew smell
^ Adhesives: musty, mildew smell
^ Standing Water: musty, mildew smell
^ Water Soaked Carpet/Trim: musty, mildew smell
Human and other interior-generated odors:
^ Secretion From The Human Body: body odors
^ Perfuming Agents: sweet or fragrance smell
^ Dirty Clothes, Shoes, Socks: musty, mildew, body odors
^ Food/Beverage: sweet, musty, mildew, fishy smell
The first step in diagnosing an odor concern is to verify the concern. To verify an odor you must determine when and under what circumstances the odor occurs and what type of odor it is.
Chemical odors are usually constant regardless of A/C setting and can be enhanced by A/C system operation. Most chemical odors are caused by fluid leaks and some are caused by improperly cured carpet and trim adhesives or evaporator core coatings.
Environmental odors usually occur for a short time and go away after the vehicle has passed through the affected area. These odors are usually only detected when a window is open or the NC system is operating in a function that allows outside air to enter the vehicle.
Microbiological odors, if in the A/C system, usually last for about 30 seconds when first turned on and will be detected in both Max and Normal A/C. Microbiological odors occurring elsewhere such as from standing water in doors or kick panels or wet carpeting may last indefinitely and will be more intense in Max A/C. Microbiological odors will not occur at temperatures below 10°C (50°F).
Human and other interior-generated odors occur while the source is present and may linger for a short time after removal. These odors can be more noticeable during operation of the A/C system. They can be detected in the outside air position and may be more noticeable in Recirc.
The first step in getting rid of odors is to find the source of the odor. Once the source is found, it must be removed and the affected area cleaned or treated.
Chemical odors can be removed by repairing or replacing the component that causes the odor and then cleaning any residue that may have accumulated from the component failure.
Environmental odors usually cannot be removed due to the fact that they occur from external sources and are an everyday occurrence. They can, however, be minimized by switching to Max A/C or Recirc mode.
Microbiological odors can be eliminated by removing the source and then treating the affected area. Standing water must be allowed to drain and dry out. A/C systems may be disodorized by using Motorcraft A/C System Disodorizer(R) (YN-18 (U.S.) or CYN-18 (Canada), or equivalent meeting Ford specification WSS-M99B187-A) as described in the Service Procedure in this article.
Human and other interior-generated odors can be eliminated by removing the source and cleaning the affected area.
NOTE
REFER TO APPROPRIATE SERVICE WORKSHOP MANUAL FOR BLOWER MOTOR REMOVAL AND INSTALLATION OR RESISTOR REMOVAL AND INSTALLATION.
Parts Block
OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 99-19-5
WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage
DEALER CODING
CONDITION
BASIC PART NO. CODE
ODOR 49
OASIS CODES: 208000, 208300, 208999, 290000