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Battery going dead


dresserman
08-12-2009, 04:45 PM
1996 Ram conversion van, the battery keeps going dead, so we disconect the battery between drives. We have traced the drain to the computer, first plug on the right side if your facing it from the front of the van. It is the first wire down on the bottom right hand side of the female plug. Why is there a power drain on this connection, our tester keep informing of a short?????
I have all the numbers from the computer if needed.
Thanks

rhandwor
08-13-2009, 05:15 PM
Use a DVOM disconnect the battery ground use the amp setting. Connect the DVOM between the cable and negative post. Watch wait until the reading drops when under dash lights shut off. Pull one fuse at a time until the drain stops. Then disconnect one item at a time on this circuit until you find the bad part. The clock and other will cause a small drain. Listen and make sure fuel pump and AST relay shut off. Sometimes you have to disconnect the alternator as they cause drains. If you have an external voltage regulator disconnect this first.

dresserman
08-14-2009, 08:09 PM
IF I disconnect all the plugs (wires) from the puter EXCEPT the first plug on the right there is still a drain on the battery, when that plug is disconnected no drain on the battery, question is why?

rhandwor
08-14-2009, 09:28 PM
http://www.alldata.com/ Buy a years contract about $25.95 They have good wiring diagrams.

dresserman
08-15-2009, 08:05 PM
Any one know if the puters on these Dodge Ram Vans can be opened up for internal inspection or to make changes ???

dresserman
08-15-2009, 08:06 PM
Any one know if the puters on these Dodge Ram Vans can be opened up for internal inspection or to make changes ???

alloro
08-21-2009, 08:18 PM
Any one know if the puters on these Dodge Ram Vans can be opened up for internal inspection or to make changes ???

They are programmed using specialized equipment. The only time I heard of someone opening one up, was to replace a couple of cooked capacitors.

dresserman
08-25-2009, 08:47 AM
So do you know what was going on that the capacitors had to be replaced???

Have been told the capacitors go bad in the alternator and draw power from the battery that makes the battery go dear IF the vehicle sets for a while between drives. Wil be checking this out.

Thanks

alloro
08-25-2009, 10:09 AM
So do you know what was going on that the capacitors had to be replaced?

The guy who wrote about it claimed that these two large capacitors within the PCM were the main reason for most PCM failures. He claimed that by replacing them, he got his PCM up and running instead of having to buy a new one.

bratt
09-16-2009, 10:49 PM
some older batteries will not hold a charge even after you charge them with a battery charger.

the plates inside go bad and you have to get another one. you can have the battery tested at most auto parts stores like autozone. they have special testers for this.

you could have a short causing battery drain and you can test for that too

Godofwarmike
09-17-2009, 02:06 AM
how much of a draw is the computer using?

The computer will need some voltage to keep settings, codes, and such in memory.

Usually this draw is very little less than a volt.

Other possible draws are radios, lights.

Or like bratt said it may just be a battery that is too old to hold a charge for long.

Doug Rodrigues
10-19-2009, 02:14 PM
I had a similiar problem with my Van. The battery was always low, although there were no dead cells and the battery was only about one year old. When I put a volt meter on the battery the voltage never got over 12.9 volts. I assumed that the voltage regulator was defective and that was built-in to the computer.

I spent the money and bought a rebuilt computer from the dealership. No change?? I then went to the autozone website and followed exactly the directions to check the charging system. What I found was that the alternator wasn't grounded? That made no sense? It was bolted to a metal bracket, right? The ground strap from the engine to the frame was in place. Perhaps because of corrosion, rust, or paint, the grounding was poor. It just developed over time. I added a second ground strap from the engine to frame ground. No change? I then added an 8 gauge ground wire directly from the battery to the case of alternator. The charging voltage jumped up to 14.5 volts. That's all it was...a lousy alternator ground, even though it was bolted to a metal bracket.

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