I think the computer in my BII burned out. After i had the alternator rebuilt it shorted out because the brushes werent installed in the regulator properly. The one brush grounded out against the case. This happened then i tried to start it and it wont. I noticed that only the intank pump now turns on. The frame mounted pump doesnt. I replaced all the relays mounted on the inner fender and the power to framerail pump is still dead. I was able to jump the relay to get the framerail pump to turn on but after that it still wouldnt start. Ive checked all fuses and what not. There is power to the ignition coil. The ign module is new. Im pretty sure its getting spark. I also think it the computer got fried because when i put the code scanner on it, it does nothing indicating the computer is probably dead. So know i think i need a new computer any suggestions. I know i need to get one from a 2.9 with manual trans but havent gone to the junkyard yet. I see reman units online for like 180.00. I need to get the truck running so i can move the damn thing. Help me out. I hope that its just the computer and cannot figure what else it would be since i checked everything. Also what does a junkyard computer usually go for.

Before you blame everything on the ECM, make sure that you check all your power and grounds. Its a better chance that you blew a fusible link or something. The ECM should have good circuit protection(fuses etc.). Check all those first, maybe you got lucky. Hopefully you have a decent wiring diagram of the ECM, and you can check all your power points.....good luck.

Brian--

I already check all the fusible links and relays and even tried replacing relays and no luck.

I have to agree with 1uglyranger it is unlikely you burned the ECM. Double check the fusible links not just visually actually pull on them lightly. If one stretches it is bad even though it may look fine. Another thing to do is go to the dealer and get a photocopy of the wiring diagrams and then check your trucks wiring to be sure it has the proper voltages at the ECM. The wireing diagram will tell what voltages you should have where.

Ive checked all the fusible links. They were ok. They all had power on both sides of the link. Ive got some wiring diagrams from chiltons but doesnt list voltages that are supposed to be coming into the ecm. I cannot get the framerail fuel pump to turn on. Is it possible i burned out the fuel cutout switch under the dash. I wasnt tripped but could that of burned out. I cant think of what else could have burned out to keep it from running. I figured it was the computer if the scanner wouldnt pull any codes from it.

Its possible that you did toast the ECM, but you need to be sure, since no one will let you return it.

As far as voltages go, all sensors(excluding o2) require a 5 volt reference signal from the ECM. Check the MAP, and the TPS ( cause their the easiest to get to). Then check all the grounds, is it possible that there was a ground strap attached to one of the alternator bolts.... Then there will be two 12 volt inputs to the ECM. They will probably not be red, Ford usually uses orange for these....don't know why... if one of them is grounded, then you have a blown fusible link....etc. etc. Just keep checking, if everything seems good, then go fork out the money for a new brain....

Keep me posted...

Brian--

Ive got some wiring diagrams from chiltons but doesnt list voltages that are supposed to be coming into the ecm
Dont even bother with the chilton diagrams they are worthless,go to your local library and pull up the wiring diagram on microphish and print it out they are very accurate and much easier to read.

Thanks Jimyrigdfj ill try that. Any other suggestions before i buy i new ecm. I can get one out a friends parts Bronco for 50 dollars. His is the same year and engine trans combo. Let me know what ya'll think.

If you think that you have checked everything(and it seems like you are), then go buy it. There is nothing else to check........

Brian--

Ford ECMs are EXTREMELY reliable. You are not diagnosing this problem right. You say you are 'pretty sure' you have spark? Ok, how about confirming that? Have you checked power to the injectors?

You say the code reader does nothing, what type of reader and how do you define 'nothing'? Is it not communicating or are there no codes or does it not even turn on?

If your friend is really a friend he'll let you try his ECM on your vehicle to see if that's the problem before you shell out $50.

I agree it's not likely the ECM and they are reliable. Nonetheless, I'd shell out the $50 regardless. No matter how reliable they may be, it's a real show-stopper in the rare case it might die on the trail. I'd carry it as a spare, for peace of mind if nothing else (maybe that's just me). I know I'm not helping w/the problem at hand, please keep us updated when you find a solution - I'm curious to know.

The code scanner i have is a quality one from the auto parts store. It cost me 60.00 so i know its halfway decent. Before the alternator problem when i used to scan it for codes the light used to blink on it and it emitted audible tones to indicate it was reading codes and giving them to me. Now when i goto scan it the light stays on and emits no audible tones. Ill check the no spark thing, but im pretty sure its getting spark. I still know that only the one fuel pump is engaging so its not getting the right fuel pressure. I thought it would be unlikely that i burned out my ignition module, ign coil, fuel pump, pump relays all at once. From my past when the electrical system shorts out like it did as described previously, ive known the computer to short out. I opened up the case of the computer and saw nothing burnt so i figures one of the chips or ic's got fried keeping all vital engine systems from functioning. If its not the computer im lost as to what happened. All the fuses and fusible links are intact, and everything else electrical that i checked worked. I cant figure it out. Its obviously not running so im not gonna have it towed to a shop, im gonna fix it myself.

Originally posted by clreinstein
I already check all the fusible links and relays and even tried replacing relays and no luck.

Sounds like you've covered this but the one time my Bronco wouldnt' produce codes the EEC relay was dead. Have you checked for power at the EEC relay plug? At the same time my fp wouldn't turn on, but I've only got single in-tank pump. But, if you're getting no fuel AND no spark, 99.9% chance it's something EEC-related.

My computer died on me a couple of years ago. I got no codes off of the code reader and everything pointed to a faulty ignition system but when all was said and done it was the computer that was bad. Kinda sucked because I ended up with a new coil, TFI module and crank trigger when I didn't need to change them. Ended up costing me lots of money that I didn't really have. On the bright side I have spares for everything in my ignition.

I agree with CPMaverick. If your friend is really a friend he'll let you try his computer before taking your money. If he was a good friend it would be free.

Where is the EEC relay? Is it on the pass fender. I replaced and even tried switching around and jumpering the relays there. I dont know where the EEC relay would be located. Hey Paul Gagnon, i did the same thing with ignition parts when i bought it. Turned out the body shop disconnected some hard to see main ground wire. Ill see if my friend will let me have the computer , then if it works offer him the money. Also what would one look to pay for one that i pull myself at a junkyard? Thanks for the help thus far.

Can't tell you what a used on will cost. I was so confused by the intermittent problem that I took it to a Ford dealer. They assured me that they would find out what the real problem was and not just replace parts. Of course they were full of shit and replaced the TFI because "it didn't stall while we had it but that HAS to be the problem" not 20 minutes after I left the dealer it stalled again so I took it back and they ended up replacing the computer. I was so mad. I told them that if I wanted to just replace everything until it worked and do no troubleshooting I would have done it myself and saved the labour. The new "reconditoned" ECM (or is it ECU) was $380. That was three years ago and I'm still mad.

Screw you Marlborough Ford in Calgary :flipoff: :flipoff: :flipoff: :flipoff: :nuke: :nuke: :nuke: :nuke:

Just curious??? Ever figure this out???

Brian--

Weve narrowed it down to being the ECU. Now i just need to hit or the junkyard then contact my friend about getting the one from him to try and see if it works. Ive been slow with it since the B2 is no longer my daily driver so i have the whole winter to work on it. Anyone else have and thoughts on this question???