Howdy y'all! I've got a manual rwd 1993 F-150 with the 4.9 L6 and california emmisions, which is my only form of transportation. A couple of weeks ago, it died while I was driving and it turned out to be a burnt out ecm (F3TF-12A650-VA). I have found it extremely difficult to find a trustworthy replacement for a reasonable price and have checked flagshipone, local pick n pulls, craigslist/ebay, etc.. At this point, I'd like to swap it with a federal emmisions ecm or possibly a california emmisions one from a different year as I can't afford to drop over $400 on it right now and and I'm hoping that finding another compatible version will be cheaper. Based on my research, it seems like it should be possible to do, but I can't figure out which ecms would work as a replacement. Does anyone know if it's possible and/or which options would work?

 

How bad is the ECM damaged? Don't know if you know or not but capacitors can be replaced and some traces on the back of the circuit board can be repaired with jumpers.

 

It burned across the board pretty good and I don't have any experience repairing electronics of any sort except for plug and plays. I tried reaching out to a company who repairs ECMs two weeks ago but they never got back to me. I also had a friend of mine (who's a circuit board wizard) take a look at it and he told me it was most likely not worth saving

 

Yeah, that looks beyond repair. Someone will be along who knows about compatability.
Any ideas what caused the arcing?

 

I don't and that's been worrying me too. It had rained for the first time in a while over here the day it burnt out on me so it could be moisture and my battery is on its last legs so I figure it could have made things worse as well. I was able to tell initially that the ecm was the issue because of the strong acrid smell inside the cabin imediately after it died and none of the fuses had popped, but aside from removing and inspecting the ecm I haven't done any other troubleshooting. Is there anything else I should check to avoid burning out another computer?

 

I don't know. The furthest I've been into them is replacing capacitors.
My guess is, that something overheated on the board and took out neighboring components.
It never hurts to check the ground cable from your battery negative terminal to the engine block but I'm not telling you that caused the ECM failure. It's just a connection that a lot of people seem to never check.

 

Battery connected backwards or an issue with the alternator's output?????? Those capacitors typically open due to age. An open capacitor will not cause excessive current flow to burn up those traces. If nothing externally to the processor caused that then some component shorted.

 

Bite the bullet
Go the 400 bucks for the new one
The truck owes you nothing at this point
You owe it a new processor if you can find one, regardless of price
It will not pass IM in Cal with a 49 state federal processor in it

 

I'm asking this for the OP so hopefully someone here knows the answer.

Since he has a 5spd manual does the ECM need to be one out of a truck with a 5spd manual or would one out a truck with an automatic work as well or at least start? If it won't work, what will be affected?

I think he's located some prospective options from a pick and pull, if it will at least start and run with a salvaged (different trans) version, he could trouble shoot for electrical issues? I'd hate to see him spend the money for a new one and then fry it too.

 

It should start but will have a check engine light on looking for missing transmission sensors and shift solenoids etc.