PCM follow up

No lights on and the reader did not give any codes, Just said it was bad. Garage said it could stop at any time while driving it. That is what was worring me. If it was bad would truck just die and then be able to be restarted or would I have to call a tow truck? Trying to learn as much as I can before going to dealer. I am sure dealer has gotten a lot better that was years ago. I bought a used car and they put the brake shoes in backward and power steeringdid not work, was supposed to fix it as part of deal. Ended up thesteering cylinder was broke and dealer paid a front end shop for the repair they should have done.

The engine needs the computer to run. If the computer goes bad, the engine won't run, so unless you're real good at pushing, yes, you will be calling a tow truck.

It will cost you nothing to at least call up the dealer service department and ask. They get paid to quote work for customers, and you are under no obligation. Just ask what installing a new PCM in your truck would cost. They have a book that tells them how long it should take and what the labor cost will be, plus parts cost. Then you'll know and you can stop being scared.

Have you tried unplugging, cleaning the contacts with brake cleaner, and reconnecting the connectors?

Be very careful and examine the pins that none are folded over.

I would go the dealer route as a very last resort. They may not even be interested because of the age and troublesome history of those.

(quoted from post at 07:56:02 10/12/22) The engine needs the computer to run. If the computer goes bad, the engine won't run, so unless you're real good at pushing, yes, you will be calling a tow truck.

It will cost you nothing to at least call up the dealer service department and ask. They get paid to quote work for customers, and you are under no obligation. Just ask what installing a new PCM in your truck would cost. They have a book that tells them how long it should take and what the labor cost will be, plus parts cost. Then you'll know and you can stop being scared.

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If NO MIL or codes WHERE does the assumption come from that the computer is ''bad''? (Besides the fact it's a Dodge?)

There are a number of rebuilders out there that will sell you a rebuilt computer very reasonably with the exchange of your old one. Replaceing it is fairly simple. They will require VIN and mileage to program the replacement.

Now that I think of it, the likelihood of a bad PCM causing your problem is highly unlikely. More likely a bad sensor or ignition component. At the very least, a PCM problem would usually result in a no-start condition or a code generated.

A word of caution: NEVER take the word of a parts clerk at an auto parts store about ANYTHING. If they were any kind of a mechanic or diagnostic expert, they would be working in a shop and getting paid top wages - not selling parts for minimum wage!

If NO MIL or codes WHERE does the assumption come from that the computer is ''bad''? (Besides the fact it's a Dodge?)

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It comes from Leroy. He seems convinced that the PCM in his truck is bad.

Maybe if he goes and talks to a service manager at the dealer, they can do some actual troubleshooting. Just a diagnosis won't put him in the poor house. Dealers will usually do a no-commitment-necessary evaluation for under $100, which becomes free if you let them do the repair.

It pays to have a buddy with a truck and trailer that can come and rescue you so you don't have to pay for a tow.

I know nothing about your truck, but Chryslers products have been known to have wiring(ground) problems under the battery trays. I had a Jeep that was in the shop for 4 days for a miss fire. Bad ground at the pcm was the fix.The shop owner felt so bad he only charged me $500.00 labor.

A 'reader' doesn't just say a computer is bad. First thing I would look at is if there is power and ground to the DLC connector. Pin 4 is ground, pin 16 is 12V hot. If there is no power or ground at the DLC, the reader the parts jockey plugged in will read nothing because it can't read codes using just its internal battery.

What symptoms does this truck have? I wouldn't count out a Chrysler JTEC PCM being bad, I have seen a few, but not common.

Maybe take it to a different dealer that you have more confidence in? A different independent shop might be more willing to work on it too.

(quoted from post at 05:33:17 10/13/22) Maybe take it to a different dealer that you have more confidence in? A different independent shop might be more willing to work on it too.

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I don't believe that Leroy has taken it anywhere yet. Just whatever big box auto parts store that put their reader on it.

Sounds like he doesn't trust dealers or auto mechanics in general, which is sad, because he needs a good one right now. There are good ones out there. In fact there are more good ones than bad. I'm lucky that I have one literally 3/4 of a mile from my house, and I have another friend that works at a GM dealership who does side work out of his garage. Both are honest and do good work. Either one would gladly tackle this problem and fix it for a lot less than Leroy is thinking.

It would just every once in a while at randon tims just skip like a plug miss firing. I thought possibly a fuel injectioner acting up and I run two mottles of injector cleaner thru it, Seemed to clear up a bit after first bottle butdid not last so second bottle. I don't even know what injector looks like. No codes showing up with engine check light. No lights on. Went to O Rileys. There instrument only said PCM problems, nothing else. Is there different quality readers? I just thought all would read the same. I just asked at garage I always use what he knew about a PCM. (I did not even know what a PCM is) He just said he cannot work on then, dealer has to do it because of something about setting to exact vehical. Said might go out like a light bulb or slowly quit working like a slow leak in a tire. One person on here said they never go bad, others saidcommon to go bad. Some as I was trying to under stand them was like that tire with a slow leak and others like that light bulb. I assume it is under the hood someplace, correct? Talking aboyt plugin in , does it have wire connect to it or a built in plug? Size of a wannut or a grapefruit? The information given to me actually if I was a mechanic that I am not could be good but to me what was being said might as well have been in Grek. I did not know there were different quality readers, thought all were the same. So readerr just said PCM Problems so I just asked the garage that I trust what he knew about PCM and that is all he could tell me is that his garage could not do anything and have to go to dealer. Could not tell me if it would be like the truck would just stop like that light bulb going out or ifafter coolingdown it would start working again of if dead in water. That dealer that did problems that was 30 years ago and probly put a person that should not have been working on cars on it. If he has had that kind of problems since he would not have grown to be one of the bigger dealers in area. I just did not want to go in to get a reading and comme out holding a bill for $500 that I don't have Just to tell me if it wassafe to drive or needed to park it and only use my totally rusted truck to get around. So what would be the chance of ot stoping completely on road like that light bulb going out Or would it be more like that tire with a slow leak that could be pumped up agan ang go for a while before it needed pumped up again. I could be looking at it under the hood and not know what I am looking at. Now do repair shops normally have a better quality reader that the pars stores? Truck is 2001 Dakota 3.9 6 cylinder. Auto 2 wheel drive if that makes any difference.

My SD died one time in front of a friends repair shop. He brought out his expensive reader and nothing, no code, no readout, nothing. he said it was a bad ECM.

Had it towed home and started checking fuses, found a blown one ,and after changing it it started right up.

Turned out the fuel heater in the filter housing was on the same circuit and was bad, unhooked that and all is good.

Really there is no way to know how or when or even IF it will fail.

For sure there is no "pumping it back up and it will be good for a while" like a slow leak. Think of it as a tire with a slow leak, but NO VALVE STEM.

I found this using google: The PCM on a Dodge Dakota is a silver box with three large plugs going into it.



It is located behind the air filter box.

This post was edited by BarnyardEngineering on 10/13/2022 at 08:47 am.

"A 'reader' doesn't just say a computer is bad."

X2

Not without showing a trouble code.

This post was edited by wore out on 10/13/2022 at 09:13 am.

I know the reader they did yse was that way, Just PCM problems and nothing else. I saw what it said.