Why won’t my PCM give out any codes???

[Denise]

Does anyone have an answer to the basic question of why my Ford Freestar would be “dead” (no start, no crank) and the PCM won’t give any codes for us to look up??? The battery is fine, it’s not a “key” issue, and someone used a tester and checked the wiring and fuses for me. I then replaced the PCM, it was supposedly programmed, but still no codes……..

Thanks for any ideas you might have 🙂

Topic

[Denise]

[quote=”Rob781″ post=172705]hope this help…. pass 1
willl not allow me to upload mult pic[/quote]

a PS: to my just posted reply to you…..previously have ruled out that “wet PCM” problem — this particular vehicle was one from after Ford corrected the problem, and out PCM is located in a different spot

[Dmitry Tolstoy]

I would insert my 2 cents about what came to mind:

1) failed neutral safety switch – does the car cranks on Neutral gear?
2) Immobilizer – could be locked up?

[Rob]

you can test the wiring harness to the computer and test if your getting signal to it…. then you can also check the conunity between the connector of the computer and the starter realy input… it will tell you if you have a good wire…. do that with the battory disconnected… if that shows good… connect the battory up and now hot wire the reley socket and see if the starter kicks over… then test the starter if its good or bad manualy… and then go from there…. so you tested that all the req signals where correct going to the computer before replacing the PCM??? you always want to check out to make sure you have everything is good before replacing the PCM… the computers should always be the last thing you replace… because on newer cars have an anti-theift systems can it could trip it and lock your car down and will never start untill its reprogram correctly… if it was programed incorrectly by acccidently your car might never start untill it is reporgramed correctly… adding a posible 2nd problem with an unknown… that the computer is locking down the car
sorry I forgot you will also have to check the ground’s on the relay sockets also

[Larry Bible]

I have not read the entire thread so this might have already been discussed. Have you confirmed that the Control Area Network is sound? You can do this with a brand specific scanner that will confirm module communications or at the DCL with an ohmmeter.

[Denise]

[quote=”MBDiagMan” post=173794]I have not read the entire thread so this might have already been discussed. Have you confirmed that the Control Area Network is sound? You can do this with a brand specific scanner that will confirm module communications or at the DCL with an ohmmeter.[/quote]

Thanks for your post, Sgt.! The Staff Sgt. in this house knows old car engines well, but not a lot about any of the new electronic / computer type stuff, so it’s really frustrating! So have not done or confirmed what you asked about 🙂

[Larry Bible]

Okay Sarge. Use an ohmmeter across pins 6 and 14 of the DCL. Post the results here. I know on a GM car, that should be 60 Ohms. I expect that a Ford guy will chime in and let us know if the terminating resistors,on a Ford are the same. As I recall pins 6 and 14 will be the third pin from the right on the top and bottom row of the DCL connector.

Hope this helps, even though you outrank me.:)

[Author]

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