I had this on my 2000 windstar and here is the link to the steps I took: I had to replace the brake light switch(was old style and wet with brake fluid from having done brake jobs) and it also allowed my Cruise Control to work again.
http://brandonsprojects.blogspot.com/2008/07/blog-post.html
the speed sensor is located on the side of the transmission, there is no physical cable like the older cars, the speedometer and sensor are electronic. If the speedometer is working and showing speed traveled but the trip meter (odometer) is not working, the speedometer itself is faulty, is the speedometer is not showing speed travel and the odometer is not logging miles travel, then most likely the speed sensor is dead.
It's in the owners manual. Turn the key to the "on" position with the odometer reading showing. Hold the trip reset button in for five seconds or more. When 0000000000 shows, release the button. The current odometer reading should show.
Check the owners manual. On the 2004 you follow this procedure. Shut the engine off with the odometer[mileage] showing. Turn the ignition switch to the run position [one position short of start]. Hold the trip selector button[the one sticking out of the speedometer lens]down for more than five seconds. The odometer will show 00000000.Release the button. The odometer reading will show. Turn the key off.
It's in the owners manual. Turn the key to the "on" position with the odometer reading showing. Hold the trip reset button in for five seconds or more. When 0000000000 shows, release the button. The current odometer reading should show.
Check to see if there is a sticker on the end of the driver's door showing the original size of tire , and compare that to what is currently on the Ranger. Any change in tire size or wheel/tire combination if it is not a similar diameter as the factory set up will throw off the speedometer.
You can only restart the trip odometer. There usually is a button on the instrument cluster that brings up the trip odometer or the regular odometer. Once you have the trip odometer showing just hold down that button for a few seconds and it will reset the trip odometer back to zero.
if trans shift is affected, then losing signal to PCM from trans if not affected then losing signal to dash or dash itself is problem use scanner to see if VSS is showing speed when dash does not
Your speedometer is broken.
speedometer
Then it is time to get it fixed.
Start with checking the fuse. Should be fuse #10.If you have other functions that aren't working also, like the odometer showing dashes, radio, or A/C, then your Windstar is leaking brake fluid at the base of the master cylinder.Ford has just issued a recall of all Windstars for this problem. Check with your local Ford dealer for details.See "Related Questions" below for much more about these problems...
press and hold the 0000 buttom while it's showing the trip mileage