good morning and thank you for inquiring with JustAnswer.This has been a common concern with the taurus due to water intrusion from the cowl into the heatercase has caused blower motor as well as resistor failures on all these model taurus and sables. I suggest having the cowl panel sealed, and a rainhat extension seal installed to correct this concern

TSB 04-15-3	WATER IN THE BLOWER CASE - BLOWER MOTOR AND/OR RESISTOR FAILURE - VEHICLES BUILT 5/1/2001 TO 12/15/2003
Publication Date: July 15, 2004

This article supersedes TSB 03-15-06 to update the vehicle model years and build date information.

ISSUE:

Some vehicles built between 5/1/2001 and 12/15/2003 may exhibit water in the blower case or on the passenger side floor, an inoperative climate control blower motor, a motor that operates on high speed only, and/or a blower motor resistor failure.

ACTION:

Inspect and seal cowl area and install Rain-Hat Extension Seal. Inspect and replace blower motor and/or blower motor resistor if there is evidence of water/corrosion. Refer to the following Service Procedure for details.

SERVICE PROCEDURE

1. Access blower motor and resistor per the Workshop Manual Sections 412-02 and 412-04. Inspect for evidence of water/corrosion. If water/corrosion are found or parts have failed, replace per Workshop Manual (blower motor 1F1Z-19805-AA and resistor F6DZ-19A706-AA).
2. Visually inspect the Cowl Vent Screen located under the RH windshield wiper to verify if the screen is fully seated. Inspect the rubber seal on the vent screen which should be fully seated against the windshield. If the cowl vent screen is not fully seated and appears warped, it must be replaced (4F1Z-54018A16-BAA).
3. Remove the cowl vent screen per the Workshop Manual Section 412-01 Pollen Filter Removal and inspect the cabin filter to confirm it is fully seated. Re-seat the filter as necessary. Inspect rain-hat base to make sure it is secure and sealed to the body. Reposition and reseal as necessary using Clear Silicone Rubber TA-32.
4. Remove the foam sealant expulsion at lower front outboard corner base of the rain-hat (Figure 1).
   
   
   Figure 1 - Article 04-15-3
   
   
5. Locate the tape as shown (Figure 2). Remove the tape and apply Clear Silicone Rubber TA-32 to the small hole as shown (Figure 2).
   
   
   Figure 2 - Article 04-15-3
   
   
6. Install the Rain-Hat Extension Seal or Shed Lip Seal 4F1Z-54022A54-AA to the outboard edge of the rain-hat (see Figure 2 for installation). The 10 mm by 10 mm (0.5" by 0.5") cut area, located 25 mm (1") from the end of the seal, will face down and locate at the 90 degree bend of the rain-hat on the fender side (Figure 3).
   
   
   Figure 3 - Article 04-15-3
   
   
7. Prior to installation of the cowl vent screen, verify that the cabin filter cover is properly snapped in place and the clip is located on the inboard side, (toward the center of the bulkhead), the cover will feel loose if not properly snapped in place. Reinstall the cowl vent screen per Section 412-01 of the Workshop Manual.