francis212

I was wandering what to test to see if the ecm is bad i been have alot of electrical problems lately. And talked to a couple people and they think it maybe the computer. I want to know for sure tho casue i would hate to spend 800$ and that not be it? Any help is very appreciated Thanks Francis

vzdude

Typically if the ecm dies, so does the truck. Lots of diagnosis would have to be done to confirm. What type of troubles......lots of help can be found here doing a search. You probably aren't the first guy to have similar issues!

francis212

My truck all of a sudden driving down the road started running funny. It woudl break up almost like it was gonna shut off then out of the blue kick back in and run fine. Did this all the way home about 10miles. So i got home and it had a p0222 code so i bought a apps for it. replaced it and thats when the real fun began. It was still runnign funny so i went to go to or loacal parts store and on the way it reved up to 2500 rpms the Ect went to 225* about so i kept driving to get out of traffic hoping it really wasnt that hot it was just a sensor problem. I got to somewhere i coudl pull off then the temp went back to normal 190* and then i lost my pedal i had no throttle response. It threw p 0117 p 0121 p 0122 p 0217. So i continued to mess with it un hooked my Edge comp box to see if that was it. Still the same thing. So i put the original map sensor back in and drove it did the same thing. but now its doing all the same things as before but then the oil pressure dropped sending a p 0522 code so i hooked up a mechanical guage to make sure my oil pressure wasnt bad and it read 75psi (cold) i think im good with oil pressure. O and when i turn my keep to the "ON" position it reads 40 psi of oil pressure on the instrument guages . I know its long but thanks for all the help i can get.

vzdude

O.K......a couple of things.....the guages are run by the PCM, not the ECM. Check all the grounds and then maybe test the alternator. Sometimes if a diode is going out it can cause some real funky things. I'm doubting that the ECM is bad or the PCM either. Start looking for a wiring problem if neither of the other things check out. ( alt or grounds )

francis212

I knew the ECM and PCM thing but i just didnt understand the whole truck running messed up thing. That why i kinda went to the ECM first Ill vat test my altenator and check the diode. i checked out my grounds on the body frame and engine i did a few tests the on the harness that went to the cmp map and iat to make sure they were gettin the right signal voltage and continuity through the grounds. Ill try that and see how i make out thanks again

vzdude

Those sensors ( coolant, apps, oil, intake air temp, water in fuel) all share the same ground. Pin 11 from the ecm ( yeah....sorry about the whole PCM deal too! The ECM sends the info to the PCM over the BUS ) It is a Black wire with a Light Blue tracer. Splice #165 to be exact. Trying to find a location pic for ya.....not having much luck yet. Hopefully this will help you get started in the right direction. Typically a splice is near a branch in the wiring harness. Loor for where the wiring harness splits to go to the oil psi sender. ( right above the ECM )

francis212

I have off work tomorrow so it looks like i have some things to look at. Thanks so much and ill get back to you when i find out some more info.

francis212

Ok so between work and the weather being terrible for the past month i managed to get the entire engine wiring harness off the truck took all the looms off and unwrapped all electrical tape checked all wired to see if there was any broken wires and nothing everything all wires are A ok. I got some wiring schematics and ECM pin outs and it looks like if those sensors are all grounded through the ECM??? Would that leave the ECM to be the problem?

dozer12216

Man, have you done some work, that unfortunatelly got you nowhere. Getting wiring taped together again is gonna be a killer.
A suggestion. Perhaps you have a friend that will allow you to put your PCM and then the ECM on his truck for test purposes. The reason I suggest is You have no ideal which component (probablly one failure involved) is causing issue. You will not be putting his computers at risk. If your computer is failing it will not kill other components, just run like on your truck.
Another suggestion is having a Dodge dealer run a scan and hook up their tester. Yes, it might cost a couple hundred dollars, but might be money well spendt. Make sure they work on many diesels.

thellums

I have my old ECM out of my '01 that you could borrow if no one closer has one that you could try. If it fixes your problem keep it and we'll figure out a fair price, if it doesn't just send it back no worries.

francis212

MY buddy has an 01 that would probally let me borrow his... his truck is the same year but its an auto does that matter mine obviously is a 5 spd, Dozer you said it wouldnt mess his Ecm up if i swap them out. i was worried about that then i would be buying 2 $1200 Ecm's. ,,,,, thellums if it will work and his computer does fix my problem ill get back in touch with u if u would want to sell thanks.

dozer12216

My suggestion was put YOUR pcm and ecm on HIS truck. If your truck has a problem that killed the pcm or ecm, guess what it will do to another????
Remember money might be well spendt with good technician and dealer test equipment.

thellums

I don't think you can use an ECM in a auto for a manual, but I'm not positive.

francis212

Yea i wasnt sure about that either event ho the pcm is what does this shifting i think...?? Is your ECM for auto or manual??

thellums

Mine's for an auto.