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Where to buy a rebuilt PCM/ECM? **UPDATE**

Posted By: DUFFMAN

Where to buy a rebuilt PCM/ECM? **UPDATE** - 11/02/11 12:46 AM

I have a 1998 Ram that seems to have a bad computer. There is no fuel, no fire and 3 different OBDII readers could not link up. There is 12v to the OBDII connector and the fuel pump does not even prime.

So anyway, I decided to spend the money on a rebuilt unit rather than a used unit, but where to order it from? I noticed there are several websites that offer them, but I don't know if I can trust any of them. Anyone order one from a place where they had a good experience?
Posted By: 70Duster

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 01:04 AM

I bought one from the local NAPA many years ago and it's still working fine.
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 01:16 AM

Just looked at NAPA's website, they're more than double the cost of the online vendors I've been looking at. At NAPA'S price I'd take the risk with a junkyard unit.
Posted By: moretoys

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 01:21 AM

I would get a wire diagram first.I have seen a few with corroded wire inside the harness near the driver inner fender.It is a power wire that feeds the asd and fuel pump relay as well as the check engine light in the dash.Before you spend money on a pcm,make sure you have the proper power and grounds at the pcm.It is possible that the pcm is bad,I would check wiring first.There is a branch of wire were 1 wire splits off into 4(or so) directions,it corrodes,loose connection there.between battery and firewall.
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 01:30 AM

We checked all the wiring in the area of the battery box and couldn't find any issues. We also cleaned up all the grounds and verified continuity back to the PDM.

What has me puzzled is that the PCM has power because there is 12v at the OBDII connector, but 3 different code readers could not link to it and there is no response to the key trick. So the PCM is not awake, but it seems to be getting power.

Even with an ASD circuit issue wouldn't the fuel pump still prime?
Posted By: moretoys

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 02:01 AM

IIRC the fuel pump relay gets power from the asd relay.Remove asd relay and check power in the box,The relay socket should have 1 battery power and 1 ign power,The computer controls the ground circuit.If you have both with voltage,then probably a pcm.9 out of 10 times I see wiring problems.But I am in the rust belt.
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 02:25 AM

I'm in the rust belt too, but the truck only has 37k miles on it and has been in storage the last 6 years so there isn't a lot of rust and corrosion. However, I have had a lot of battery problems due to sitting and it's had to be jump started frequently. So I'm thinking I some how power surged the computer.

The reason I don't think it's the ASD circuit is that I can't communicate with the computer. If there was a problem with the ASD circuit the computer should throw a code right?

I'm very reluctant to replace a computer because I've NEVER had one go bad in a vehicle, but in this case it looks like all the symptoms are pointing to it. I just wish I had one available to try first.
Posted By: moretoys

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 03:01 AM

If you only had a asd relay problem, then yes you're right,it should throw a code.
Checking for power at the asd relay is just the easiest way to see if there is a wiring problem.The same wire that goes to the asd relay also goes to the pcm, the ign coil,fuel pump relay,check engine light on the dash,and other places.I'm assuming that the check engine light does not light up when the key is turned on.The problem happens at a splice that goes many different directions.But you might be right about the surge.Try tapping on the pcm,Might jar something and make it work,then you will know for sure,also open it up and take a smell,if it fried,you will smell it.Small market for finding chrysler pcm's specialy at a reasonable $$.try google,I bought one from a place in florida once,I could not get locally.There are other rebuilders out there beside auto chain stores.Gonna take some work finding them.usually buy local for that stuff if possible,rebuilt units can have problems,easier to get exchanged that way.From what I understand,pcm's get repaired of there problem and resold,they do not get completely gone through.I have had a few fail within warranty period.
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 03:16 AM

Quote:

Checking for power at the asd relay is just the easiest way to see if there is a wiring problem.




I didn't check for power to the ASD relay, but I did swap it with the wiper relay and the wipers still worked, so I know the relay itself is good.

Quote:

I'm assuming that the check engine light does not light up when the key is turned on.




Correct.

Quote:

The problem happens at a splice that goes many different directions.




I think we found the slice you're talking about, directly below the battery box, black with yellow stripe wires if I remember right.

Quote:

But you might be right about the surge.Try tapping on the pcm,Might jar something and make it work,then you will know for sure,also open it up and take a smell,if it fried,you will smell it.




It's worth a try.

Quote:

Small market for finding chrysler pcm's specialy at a reasonable $$.try google,I bought one from a place in florida once,I could not get locally.There are other rebuilders out there beside auto chain stores.Gonna take some work finding them.usually buy local for that stuff if possible,rebuilt units can have problems,easier to get exchanged that way.From what I understand,pcm's get repaired of there problem and resold,they do not get completely gone through.I have had a few fail within warranty period.




I found a place called autocomputerexchange.net I was going to order a computer from but found some negative comments on the web about them, thus this thread. I did find a couple of used ones at local junkyards but I'm concerned about programming. Do I need to have the VIN programmed? Will I still need to have the computer flashed at the dealer? Or due I just buy a tuner and do it myself?

Oh, one more thing. When I hook up the OBD II reader and ask it to scan the chime goes off. Other than that with the reader hooked up, the key on and the door open there is no chime.
Posted By: J_BODY

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 03:24 AM

If there is any doubt about a pcm I put it on the bench and wire up an ALDL connector that I cut out of a car at a junk yard. Get the connector pin outs and wire up the B+, grounds, and SCI transmit, SCI receive and hook the DRB up and see what happens.
Posted By: dOOc

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 03:40 AM

ANYone know how these are REbuilt ? ... isn't all the E-works set in epoxy ? ... how does that work ?
Posted By: teflon

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 11:27 AM

Checking for power at the diagnostic connector is not going to give you all the info you need to condemn the PCM. Get a wiring diagram and check for power and grounds at the PCM connectors themselves. Also you will want to check bus voltage, which you can do at the diagnostic connector. Can you communicate with any other module on the bus??
Posted By: therocks

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 12:04 PM

That and they have to be reprogramed.We got some remans from Advanced and never had any problems.Had to send them to the dealer to have them programed.Most were GMs though.In 30 years Ive only seen about 2 or 3 bad Mopar or Fords that were bad.Now GM thats another problem especially the old OBD1 systems.When they flash them they also update them.Rocky
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 12:22 PM

Here's the problem. The truck is about 30 miles away stored in my Parent's shed. I can't get to it during the week and I have limited time to look at it on the weekends. The truck was supposed to be moved 2 weeks ago so we could pack everything in for winter. So at this time I need to take the risk and bring a computer next time I go there. If it doesn't work then I can do some more diagnosis while I'm there.

Back to the OP. I need to get a computer but I don't have a lot of time. So it sounds like I'm better off with a used unit so I don't have to run it to a dealer to be programmed.

There is some good info here, and if the computer your suggestions will come in handy.
Posted By: 70Cuda383

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 12:49 PM

I've heard of a few guys who just swapped computers without any dealer flashing/vin programming, etc, and the truck would run fine.

maybe they were non-security trucks, I don't know.

if your truck does not have the security package on it, then maybe you can get by with a junkyard PCM, just to troubleshoot.

find one out of a truck that was clearly running and driving all the way to the scene of the crash use it to troubleshoot, and if the truck starts right up, then you know it was the PCM. if your junkyard piece fails quickly, then invest money on a more expensive reman'd unit with some sort of a warranty.
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 10:55 PM

Well I bit the bullet and ordered a used computer. It should be here on Friday. It's out of the same model year, engine, trans and a running accident truck so hopefully it's my problem. I think it's down to this; since I can't link up to the computer the problem is either the computer itself, or the wiring for it. If the engine doesn't start with the new computer then I have some wire tracing to do. Luckily I do have the factory service manuals for it, so at leas ti have that going for me.

Posted By: 68FuryIIIColo

Re: Where to buy a rebuilt PCM/ECM? - 11/02/11 11:12 PM

The PCM on OBDII will throw warning and MIL lights. I think the brake or abs light will light up until you get it flashed with your VIN. Your truck should still run if it's the PCM that is actually throwing codes.
I have had pretty good luck with www.car-part.com in finding specific parts. It is a network of all the junkyards with a stock of all parts and vehicles they have in their yard. You can sort it by distance or price or part grade. Check it out.
Posted By: JohnRR

Re: Where to buy a rebuilt PCM/ECM? - 11/03/11 02:30 PM

Quote:

Well I bit the bullet and ordered a used computer. It should be here on Friday. It's out of the same model year, engine, trans and a running accident truck so hopefully it's my problem. I think it's down to this; since I can't link up to the computer the problem is either the computer itself, or the wiring for it. If the engine doesn't start with the new computer then I have some wire tracing to do. Luckily I do have the factory service manuals for it, so at leas ti have that going for me.






You are still going to have to go to the dealer me thinks , it needs the VIN and I think the mileage programmed into it .
Posted By: indytex96

Re: Where to buy a rebuilt PCM/ECM? - 11/03/11 05:35 PM

Quote:

Quote:

Checking for power at the asd relay is just the easiest way to see if there is a wiring problem.




I didn't check for power to the ASD relay, but I did swap it with the wiper relay and the wipers still worked, so I know the relay itself is good.

Quote:

I'm assuming that the check engine light does not light up when the key is turned on.




Correct.

Quote:

The problem happens at a splice that goes many different directions.




I think we found the slice you're talking about, directly below the battery box, black with yellow stripe wires if I remember right.

Quote:

But you might be right about the surge.Try tapping on the pcm,Might jar something and make it work,then you will know for sure,also open it up and take a smell,if it fried,you will smell it.




It's worth a try.

Quote:

Small market for finding chrysler pcm's specialy at a reasonable $$.try google,I bought one from a place in florida once,I could not get locally.There are other rebuilders out there beside auto chain stores.Gonna take some work finding them.usually buy local for that stuff if possible,rebuilt units can have problems,easier to get exchanged that way.From what I understand,pcm's get repaired of there problem and resold,they do not get completely gone through.I have had a few fail within warranty period.




I found a place called autocomputerexchange.net I was going to order a computer from but found some negative comments on the web about them, thus this thread. I did find a couple of used ones at local junkyards but I'm concerned about programming. Do I need to have the VIN programmed? Will I still need to have the computer flashed at the dealer? Or due I just buy a tuner and do it myself?

Oh, one more thing. When I hook up the OBD II reader and ask it to scan the chime goes off. Other than that with the reader hooked up, the key on and the door open there is no chime.




Absolutely stay away from autocomputerexchange!!!! They took me for approximately 200 bucks I don't have enough room for the whole mess, but they outright lied to get my business and the end result was I had to order a rebuilt unit from Dodge only to have to eat the core price as these jokers cut a 2" hole in my old unit plus truck was down for almost a month waiting. BEWARE!
Posted By: fox

Re: Where to buy a rebuilt PCM/ECM? - 11/04/11 12:09 AM

Is that the place on E-Bay? I know many who bought thru them and were happy. Quick service too with next day air. Cheapest we found.
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/04/11 12:47 AM

Quote:


You are still going to have to go to the dealer me thinks , it needs the VIN and I think the mileage programmed into it .




Probably, but it should at least run without the dealer programming it. Right now that's all I care about.

BTW The first place I ordered the computer from fell through. They say they can't find it. Luckily there is another local yard that has one. Hopefully I can pick it up tomorrow so I have it for the weekend.
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/04/11 10:57 PM

Just picked up the used computer tonight. With any luck I'll find out soon if it is the problem, if not I'm going to be tracing wires.
Posted By: DUFFMAN

Re: Where to buy a rebuilt PCM/ECM? - 11/05/11 01:04 AM

IT'S ALIVE!!!!

The used computer worked! The truck runs.

Thanks everybody for your help.
Posted By: MrBill

Re: Where to buy a rebuilt PCM/ECM? - 03/25/13 10:27 PM

I had to jum in with my opinion of Autocomputerexchange (ACE)...My 99 Durango had an intermittant stall in hot weather traced to the PCM. A replacement from ACE fixed this for about 2 years. Then it failed again with the speed (cruise) control going cyclic or intermittant. Got another ACE replacement that was bad upon arrival. They honored that warrenty and sent me another bad one that would not allow the vehicle to upshift. Third try with them was the charm and this one has been good for 2 years..Just so you know, there is no assurance that they test all or any functions of these modules. They send what they have on the shelf. I also bought one for my 95 Avenger (OBD 1+) that was good. Just buyer beware and hope you get one that works...
Posted By: Dakota_Don

Re: Where to buy a rebuilt PCM/ECM? - 03/25/13 10:40 PM

My brothers 2000 ram pcm went out ( inj 4 driver) and i was going on a trip with it, so i pulled one from a JY and thats been bout 6 yrs ago and its still in there..no codes or lights at all i was surprised..
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