We have a ford windstar 2000 and recently my wife

SOURCE: Fuse Diagram for 2000 Ford windstar

here is a link to where you can down load a owners manual to help you
https://www.fleet.ford.com/maintenance/owners_manuals/default.asp

SOURCE: Thumping noise when braking - 2001 Sienna

Could be a number of things that you cannot "see".

First, make sure the tire pressures are within the van manufacturers specifications. The tire pressure label will be on the driver side door pillar on a little sticker. Also confirm that the tires haven't been replace with an overly greater / lesser size.

Broken radial belts inside the tires are another cause - and is also dangerous if the tire heats up enough - it's a blowout waiting to happen.

Check for ANY unusual "ripples" on the inner and outer sides of the tires, and for any unusual wear patterns.

Putting the tires on a balancer will NOT show these tire problems.

You could try narrowing the problem down to a particular tire, and putting the spare on and see if the problem goes away.

Also, I have seen "off brand" or "blem" tires do this a lot.

SOURCE: 2003 ford windstar

Check your transmission fluid level if at all possible. If your fluid is low you won't be able to engage any gears as there isn't enough pressurized fluid to shift the clutch or selector in the transmission box. If that's fine, next check the selector link and check it is connected to the transmission (not totally unheard of for it to come loose). Still no joy then it's the clutch...sorry.

SOURCE: Check Engine Light / Chrysler 300m

i have a 2002 300m and my check e light came on 2 days ago i ttook it to a mechanic in dallas and he told me it would be 500 to fix it so i took it to autozone to have them put the free dianostics test and it ended up being the gas lid not on properly they said it was common on this model they reset my battery for me and my light is still off today