My 2000 2500 van 5.2.I just picked this up recently I just had rear end rebuilt.Now that that's not screaming at me.Ive started using it as daily work vehicle.Now it has started intermittantly overcharging.Its weird because Ive been reading all the threads I could find & none described exactly what my gauge is doing.It shows close to 14 volts when its normal. When it starts overcharging then the gauge drops to the bottom.aii the threads Ive read said thiers just showed the over voltage on the gauge.Hoping that might be a clue?? Its putting out around 15-16 volts.It does this mostly when 1st start in the am.If it does it when cold then you cant keep it running w/out foot on gas pedal once it warms then it will idle. It doesn't have to be cold to do it you can be driving around all day & it will kick up & down at will.I suspect the computer from everything Ive read.I tried tapping on it w/no change since I read sometime poor solder connections. Thanks for any input this is an awesome forum.Thanks for any help on this issue

 

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If the PCM is required what the best source for the rebuit PCM? I seen several sources online.Are there any that offer this forum a discount? Thanks again for your input!

 

both of the PCMs that took a crap on me showed overvoltage charging conditions a day or so before they died.

I used all computer resources out of Ft Lauderdale. There service was good.

 

Today for the 1st time I got a code P0138 & it quit . Had to have it towed back. Could this be another symptom of overcharging?

 

Well it looks like Im PCM shopping I cleaned all the grounds, still overcharging. So far dodgeautocomputers.com has best price $201.80.on sale.allcomputerresouces.com wants $289.00.Both have lifetime warranty.

I also replaced the coil & it started right up.So now it sits til I get a PCM.

thanks for the help again!!

 

What do you mean when you say the gauge "drops to the bottom"? If dropping to the left then your alternator is under charging, not over charging, and in that case your alternator may be bad and not the PCM. Had this happen in my van shortly after I bought it. Now I did clean and also recommend cleaning all the grounds and even the positive connections before replacing the alternator or PCM.

I would highly recommend taking the alternator out and have it tested first.

 

That is strange.When I noticed the gauge drop to 8 which is the bottom. I had it checked at autozone.They said it was putting out almost 16.I have verified that my self with my volt meter everytime the gauge drops the voltage raises 15-16.This is the only symptom I cant find any thing on.The only thing that I could figure that maybe the overcharge is opening the circuit to the gauge?? Its like the gauge is off.then the voltage drops to normal & it starts to rise.I really appreciate any imput!!!thanks for your help

 

I ve been so busy this week I haven't had time to do much else I have been thinking about the way the gauge is working.when I turn on the key If its in the overcharging mode the gauge does rise but it stops at 8 if I start it it will be overcharging.If when I turn key on the gauge rises to normal voltage then then when I start it it will be charging properly.Please if this makes sense of this to anyone I appreciate your help.Im thinking that what ever is happening its must not involve the alt. because its in that state before its running.

 

The volt gauge and voltage regulation are controlled by the PCM. Your symptoms lead me to believe your PCM is going on you.