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Dodge Repair/'04 ram: pcm replaced, now won't start

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Question
QUESTION: I installed a rebuilt ecu/pcm in my 04 dodge ram 1500 ( 5.7 hemi) and it started 4 times and died. Now it will not even turn over

ANSWER: Hi Gilbert,
That sort of behavior sounds like it is related to the vehicle theft security system. If it shut down in a few seconds after several tries, and then won't turn over, that is likely due to the security system not being recognized by the replacement pcm. There is a vtss status light on the dash board and if it is "on", then that may veify this is the cause.
Did the vendor of the replacement unit mention a need to acquaint it with the vtss? Have you contacted the vendor for instruction about this aspect of the replacement process?
Whenever the pcm is replaced it has to be programmed to recognize the vehicle by inserting the VIN number into its memory using A Chrysler Diagnostic Readout Box (or equivalent). If your old pcm will still work long enough to get to a dealer or qualified shop I would try that approach to properly installing the rebuilt pcm.
Roland

---------- FOLLOW-UP ----------

QUESTION: where is the vtss indicator light or what does it look like on dashboard? I do not see it when I turn the key over.

ANSWER: It is a LED light located in the instrument cluster, between the gear shift position indicators and the engine temperature gauge. It might be labeled "security" or it may just be that light without any label.

---------- FOLLOW-UP ----------

QUESTION: Reinstalled. Old PCM and truck now starts but original problem still exists ( vehicle not charging).  Found bare wire on o2 sensor that was replaced on 4/14. Wires were grounding out, I guess, replaced sensor before hooking up battery on new PCM. Is this a suggestion that vtss is problem?

Answer
Yes, if the pcm was not programmed with the VIN of vehicle than I suspect that is why it is behaving as you described. But do you have any firm indication that the pcm if faulty? If it is not charging the battery then of course the first thing to check is the alternator. If the alternator is good then the wiring from the pcm to the alternator should be checked, and finally if the pcm were defective as regards its control of the charging of the battery then there would likely be a fault code that alerts you to the pcm being faulty. Did you get a fault code that said the pcm was bad?
It could have given you a code that says the charging circuit (to the alternator field coils is bad as an alternative explanation for the problem.
Turn the key "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see if the mileage reading is replaced by 4-digit number preceded by a P. Let me know and we'll go from there.  

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Roland Finston

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Get a Free Fast answer to your repair question about a Chrysler/Dodge/Plymouth car, minivan, SUV, or truck. Problems with electronically controlled engines and transmissions as well as body wiring problems are my specialty. This free troubleshoot advice forum helps you diagnose faults, minimize repair costs or do-it-yourself.

I answer questions seven days a week and respond to you in about 30 minutes. "Maxed Out" means I am answering another question or asleep overnight so try again later.

I have do-it-yourself experience (50+ years) and a library of 100 1982-2012 Chrysler factory shop manuals and 20 multi-manual Chrysler Corp. CD's.

I was voted "Top expert" from 2010-2015 here at AllExperts, and have answered 20,000+ questions.

Experience

Five decades as a 'do-it-yourselfer' on domestic and imported cars

Organizations
Yahoo Autos Group called The Chrysler Lebaron Club (co-moderator)

Education/Credentials
Degrees in Physics/bruised knuckles.

Awards and Honors
"Top expert" of 2010, 2011, 2012, 2013, 2014, and 2015 here at Allexperts. Quickest "average response time" at Allexperts (currently no. 1).

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