my 2000 windstar throwing transmission codes. p0743, p0750, p0760.
checked wiring from transmission to pcm. seems to be good. nothing obvious.

after reading around some suggested might be pcm or wiring issue.

how do you replace pcm. comes out from under dash. dont understand how to get to it.

any thoughts on this.

van does drive. reverse and high gear only. pretty sure high gear. you can start slowly and get it up to speed. no up-shifting

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Sounds like the system is in limp mode. Many things can cause this. PCM (cpu) may not be getting correct info or certain info is absent. Before replacing the PCM which will bring it's own problems, a good scan tool can narrow down the problem and save some time and $$$. Suggest you have some bidirectional checks done before replacing anything. If the vehicle has anti theft capabilities the computer will need to be reprogrammed to accept the new computer. It is possible the PCM has a problem ,but what if you go through the trouble and cost to replace it and still have the problem ?

 

I have found relays in fuse box under hood by battery is missing.
switched system power relay #1, and relay #2.
not sure what they control.
replace them and see.

I do have a service manual pdf for 2000 windstar I think I can share.

 

If it is a factory service manual great.
If otherwise , others don't always have all or sufficient info.
There are almost always unused relay positions in the panels. Not all models have all the features and therefore the relays are not required.
If you can find the description in the service manual of just what the relays control fine. If not, the owner's manual will provide the relay info and position.
There are many inputs that determine what the computer does and if any of them are incorrect or missing the computer reacts based on that info.
A good service manual will show the code and possible causes.

 

I got a pdf file ol. seems to be pretty complete service manual for the 2000. probably real close on other years, if not the same.

looking over the wiring diagrams, seems the 2 relays that are out, headlights.
but also look like possible other connections on that circiut that may relate to transmission not shifting. not sure.

all i got is reverse and high. would like more thoughts on "limp mode"

this is not my daily driver. picked it up for work if i get it figured out.

be glad to share pdf file service manual. if possible.