Archived Overcharging Problems

[Malcolm]

I have a 97 2500 full load 4x4 automatic with 185,000 km (about 115,000 miles). Bought it new. In 7 years, I'm on my 6th battery and my 3rd alternator. My battery gauge is always in an overcharge position after it has warmed up. About 15 to 15. 5 amps. My last alternator actually burned up after 5 mos. These are new factory alter nators and batteries. Several batteries ago, it took up to 18 minutes for the battery gauge to come up to normal or into the present overcharge situation. My Chrysler dealer thinks that the Power Control Module is the problem. Does anyone out there have an idea what the problem may be before I pay $700 for a new PCM? Also several batteries ago when it was taking 5 to 18 mins for the gauge to come up to normal the truck was very difficult to move when you put it into gear. It would be 2200 to 2500 RPM before the vehicle would begin to move. It was as though you were hooked up to a 70 foot mobile home stuck in the mud. Thanks for any help out there... Mal

 

[crabman]

Malcom,

Do you have VTVM? If so then try this:

Key off

Remove the generator white 120 amp fuse in the PDC . (large black box on driver's side fender.

On the Alt. back there are 4 wire connections. Starting from the wire harness hold down nut.

#1. DarkGreen is the generator field driver wire

#2. DarkBlue is the ASD relay output

#3. Black/White is the ground

#4. Black and is the large wire that is sort of surrounded by plastic.

Disconnect all the wires at the back of the Alt. & disconnet the powertrain control module connector (located on firewall by heater/ac stuff. Check the resistance between #2 and pin #20, wire is Dark Green. The PCM has 3 rows of pins, #20 is the lower right hand side looking at it from the wire side.

If the resistance is below 5. 0 ohms, it is the PCM, if not, there is a open gen. field driver ckt. (broken wire between PCM connector and alt. )



Clear as mud!

You can also get a reman. PCM for $300-$400.

Good Luck!

crabman

 

[Malcolm]

Thanks for the quick reply, Crabman. I'm not very mechanically inclined. What is a VTVM? The $700 for a PCM is Canadian Funny Money, not real U. S. funds. Again TKS.

Mal

 

[crabman]

Malcom,

VTVM=vacuum tube volt meter, it is a catch-all phase now for a volt meter that reads AC, DC, and Ohms. You can buy them now for less that $20. The more functions they do the more the $.

Get someone to help you, it is not to difficult. Just follow the steps I posted and you will be fine.

Any problems, just post here and someone will help you.

crabman

 

[Malcolm]

Crabman, Thanks again... I will give it a try with the help of my mechanic & will let you know how it works out. . Malcolm