I've got a 94 ranger with a 4.0 manual transmission 2x4 the ECM is bad the number is f47f-12a650-cma
I've found a ECM from a 95 ranger 4.0 manual trans 2x4 the ECM number for it is f57f-12a650-bcc
Will the 95 ECM work on my 94

 

No, 1995 and up uses the 104 pin EEC-V computer
1994 and earlier used the 60 pin EEC-IV computer
So connector won't plug in and 40 more wires would need to be added.

EEC(ECM) part number f47f-12a650-cma break down
f4 = 1994, F = 199, 4 = 4, a 1988 ECM would be E8, 1993 would be F3
7f = Ranger model

12a650 = part number for EVERY ECM Ford ever made, from 1979 to 2016 and still going

cma = software revision on chip inside, Ford never released what they mean, they are different for manual and automatic, but there are hundreds of 2, and 3 digit codes at this location, could matter but doesn't seem to when swapping ECMs

There will be a 3 or 4 digit Stamped on which will matter
Read here about that stamped on code number: Fuel Injection Technical Library » EEC Program Codes

You will need a 1990-1994 ECM from a 4.0l manual trans Ranger, also EGR matters, most didn't have EGR system but some did, you need one that matches yours.


ECM's rarely fail, not never it just isn't common, have you opened it up and had a look inside?
Should look like this: http://www.auto-diagnostics.info/ford_eec_iv

 

Yes I opened mine the board is burnt beyond repair