93 ATX with charging system problem.

[the4biddendonut]

My 93 ATX SHO isn't charging the battery for some reason. I was driving one day and the battery light turned on and eventually I ran the battery dead. So I pulled my alternator and had it checked at Pep Boys and they said it was a bad alternator. I replaced the alternator, battery cables, alternator cable and the ground strap all at the same time and now it does the exact same thing. I charged the battery and drove it for about a day, and eventually the battery ran dead again.

I'm at a loss as what to look at next. All I can think to do is check the connector on the alternator, but I'm not sure what to look for. How can I tell if the connector is and the wires are working correctly?? Should there be a voltage? and which wires should have voltage and when should they have it?

Any help will be appreciated.

 

[ohfosho]

its is a rare occasion that a bad Alternator DOESNT take out a weak/old battery.
or vice versa.

so, go and get your battery tested now.

 

[the4biddendonut]

Sorry, I forgot to mention that part. I did have the battery tested and it did test out as a good battery

 

[doclees]

Did you have the system rechecked? Did Pepboys do the work?

 

[the4biddendonut]

I did all the work myself.

Last night I was out driving and the battery light turned on again after I changed all the cables and the alternator. So I pulled over because the electronics were were turning off and on. I was lucky I made it to a parking lot. I left the car over night in the parking lot and took the battery home with me so I could charge it. I came back today with the charged battery and installed it. Immediately I brought the car to Autozone to have the charging system checked out and they said they couldn't see anything wrong. I have a feeling if I keep driving that I'm going to find myself in the same situation as last night when the battery eventually runs dead on me again.

 

[doclees]

Did autozone give you a detail report or just say "it all looks good"? Best investment I made was for one of their $20 digital multi-meters.

 

[projectSHO89]

Next time, test the replacement alternator before you leave the store.

You'd be amazed how many replacement alternators are crap out of the box.

Steve

 

[the4biddendonut]

I wish I would have thought to have them check it before taking it home and installing it.

I already have a meter. Does anyone know how I can check the harness and which wires should have voltage and when they should have it???

 

[projectSHO89]

Measure battery voltage with engine off. Should be around 12.6 if the battery is fully charged.

Start engine. Voltage should rise to between 13.8 and 14.2 and remain relatively steady (it is normal for it to rise slightly while running or at higher RPMs).

The meter can only check for basic functionality. It cannot test for charging current capability nor can it check for excessive ripple, etc

Steve