New PCM and alternator not working

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ChrisM

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Just got a reman PCM flashed with my 05 5.7 SLT info, got it installed and ran for a while but check engine light never went off and alternator is not charging battery where is should be which gauge shows and I confirmed with DVM. Output is only 11.5V and I also got more codes thrown that I have never seen. P0335, P0443, P0498,P0622, and P0403. I wonder if these are just because of the rough startup while PCM recorded info initially because the truck runs ok except for the low alternator output. Does the alternator output go through the PCM or controlled by it? I don't know if I should get a new alternator or request another PCM. Alternator was fine before. Problems I was having were tranny codes which I got fixed and codes would come back, truck rpm would jump up for a split second, radiator gauge would say truck is overheating when it wasn't and some other quirky stuff.
 

HolyRamBatman

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P0335 Crank Pos Sens Circ
P0443 Evap Purge Solenoid Circ
P0622 Alternator Field Not Switching Properly
P0403 EGR Solenoid Circ


P0489 Exhaust Gas Recirculation Ctrl Circ Low

I didn't find 498 so I posted 489 in case you're dyslexia was active.
 
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ChrisM

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All computer resources...they seem to be legit
 

BigSloth

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Alternator charging is regulated by the voltage regulator internal to the PCM. Those are all circuit codes, so it's possible the PCM could be the cause of them as well since it is part of the circuit. How did you have it programmed? By the dealer? If the software version and configuration are not right it will cause problems. Also if all the relearn procedures were not done it could have negative effects.
 
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ChrisM

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The place I purchased the PCM from got my VIN number and miles and were supposed to program that info into the new one. How they do it I don't know but from there website allcomputerresources they look to be a reputable source. They said they would send a replacement but my truck has been down for a week already waiting for this one to be programmed and shipped and they can't send a new one till Monday which really makes me mad
 
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ChrisM

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Didn't have it checked but it was working fine before along with all the other parts the truck is throwing codes for. Hopefully another PCM will do it but if it doesn't what do I do then? I can't even trade it in because the truck won't make it a mile without turning off now.
 

Redtruck-VA

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I would talk with the PCM place and explain what new problems that have come up with using the new PCM. My guess is it is a faulty PCM. I posted somewhere on here a mod to regulate the alternator bypassing the PCM.
 

BigSloth

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It's probably a bad PCM, if you get another and it does the same thing, bring your original PCM and the new one to dodge and tell them you need the new one flashed to be like the old one.
 

MegaMouseGW

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Yank your alternator out and have it checked. At 140k+ miles it might be failing. If it checks out then it is the PCM. Do you have the original PCM still?? If you do reinstall it and see if the problems persist. Again if the problems do not go away then it is the alternator that has gone bad.
 
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ChrisM

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Ok put the original PCM back in and truck ran fine with alternator charging, for 5 mins and then shut down. Only Got P0335 code this time but it would not start. I replaced the crank sensor a couple weeks ago, checked the wiring and everything looks ok to me but obviously there is an issue somewhere.
 

Redtruck-VA

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A bad Crank sensor will definitely keep you from starting. Crank and cam sensors are closely related and physically share a ground wire. I would check the wiring and if nothing is obvious I would change both sensors.

There was some tone ring failures on 03/04 models reported, but I haven't heard anyone mentioning it for some time...
 
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ChrisM

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I changed both sensors a couple weeks ago, the truck ran ok for a couple days and them started the same behavior. Does anyone have an electrical schematic for an 05 SLT 5.7l? If I can check continuity from the sensor harness to computer it may show a bad wire before I have to cut all the braided wire sleeve open for nothing.

Edit...I just took crank position sensor out and it had oil on it, is that normal? I am thinking it would read a magnet on the flywheel and therefore oil shouldn't be in that area. Am I wrong and oil on the sensor is normal?
 

MegaMouseGW

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Ok sounds like you have a bad rear crankshaft seal, or if the oil was red then you have a bad front transmission seal. There should be NO oil in the area between the rear of the block and the front of the transmission. I would at least have them checked by a reputable mechanic to determine how bad along they are. Not sure if the oil would make the sensor go bad but it is a possibility. As far as the wire hunt goes you may be able to find a schematic online somewhere. Not sure though.
 
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ChrisM

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Damn that's what I was afraid of...a lot of money to fix that problem!!! It's definitely engine oil and if its not supposed to be there I'm sure that's what's causing this problem. Like my life isn't full of a million problems already
 

Redtruck-VA

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Wait a minute, the tone ring is bolted to the crank shaft... look at the location of the sensor. That is where the tone ring is located on the crank. There is oil in the crankcase.

You can download the service manual from here.
My Dodge: Dodge Owners Service Manuals - Dodge Cars, Minivans, SUVs

Look in the engine section and you will see a diagram of a partial crank with the tone ring mounted. Typically if a tone ring is broken it takes out the sensor. This sounds like to me a damaged plug or bad wire. The cam and crank share a common ground to the PCM. On my 03 the wires are: Cam (C2-34 TN/YL ), the crank is: (C2-29 GY/BLK)
The common ground is: BLK/LB.

I usually unbolt the PCM from the firewall and pull it out to where I can work on it, pull the plugs and unwrap it to where I can separate the wires to identify them. Remove the battery ground wire before starting.

Here is a picture to show how much you can really get the PCM out to work on it.
imag0007zz.jpg
 
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ChrisM

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Thanks for that info redtruck. I can't get that page to open on my ipad to see what part of the engine the crank sensor sits in but your sure it is in the crankcase? The common ground for those 2 sensors and PCM is at battery negative? I see a lot of wires grounded directly to the frame especially in the engine compartment...none of those are connected to the ground on those sensors?
 

Redtruck-VA

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Thanks for that info redtruck. I can't get that page to open on my ipad to see what part of the engine the crank sensor sits in but your sure it is in the crankcase? The common ground for those 2 sensors and PCM is at battery negative? I see a lot of wires grounded directly to the frame especially in the engine compartment...none of those are connected to the ground on those sensors?

Yes, the tone ring is bolted to the crank. There are two types of grounds used, one is the common chassis ground. The other is a filtered sensor ground that is dedicated to sensors. I have on my truck run an additional chassis ground wire from the PCM case to engine head, TB and chassis ground to pull it all together. Some folks say they have felt greater throttle response, I didn't feel a change. The wires you want to check will be from the sensors to the PCM plug C2 as I mentioned previously. These are common to the sensors and are not necessarily chassis ground. You can check this sensor ground BLK/LB wire which can be found on you various sensors as a rough check between the various sensors themselves. You need to really read up on this to completely understand what is being done so you can effectively conduct tests. Inside the PCM itself is a mystery, but the wiring is well documented. Good luck..

Note: the crank sensor is on the passenger side lower rear of the engine block. Jack the beast up and crawl under to unplug and inspect the connector. The cam sensor is passenger side forward in a recess in the side of the front cover. I unbolt the sensor and carefully pull it out by the wires/plug while wiggling the sensor a little. Once I have it out then it is easy to unplug the sensor from the connector.
 
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