2004 Ford Taurus - 2004 Mercury Sable

Question edited for clarity.
Question moved to correct year make model category.

Check the fuses and relays.

Ford Taurus (2000-2007) fuses and relays

https://fuse-box.info > ford > ford-taurus-2000-2007-fu...

2003 - Here you will find fuse box diagrams of Ford Taurus 2000, 2001, 2002, 2003, 2004, 2005, 2006 and 2007, get information about the location of the fuse ...

2003 Ford Taurus fuse box diagram - StartMyCar

https://www.startmycar.com > Taurus > Fuse box
The 2003 Ford Taurus has 2 different fuse boxes: Passenger compartment fuse panel diagram. Power distribution box diagram. * Ford Taurus fuse box diagrams ...

Ford Taurus (1999 - 2007) - fuse box diagram - Auto Genius

https://www.autogenius.info > ford-taurus-1999-2007-f...
Jul 2, 2018 - Ford Taurus (1999 - 2007) - fuse box diagram. Year of production: 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 ...

Wanda, Check out the video and links I posted to see how to remove and replace Taurus water pump.
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
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P0 Wells Ford EGR DPFE Training with Sgt Tech P0400 P0401 P0402 you need to test it first.

Serpentine belt diagram 2002 ford taurus 3 0 2002 Ford Taurus
should be the same for 2003

It is standard equip so the answer is yes.

Good for you.

either you took out the wrong bolt by the trans.... or the pin is stuck ... give it a whack with a mallet
should of taken out 2 ,13 mm bolts

look under hood for diagram

You can try to replace with a similar unit, but typically Ford ECUs have to be "reflashed" by the dealer. Ford has numerous calibration codes and various other vehicle specific information that can only be managed with Ford certified (dealer) programing devices. I hope this helps