Chrysler Repair: 1996 Dodge Avenger ES 2.5L V6 Battery?, dodge avenger, 1996 dodge avenger

Question
I'm having issues with my Avenger not holding a charge (sometimes).  CEL codes 12 and 21 and ABS light comes on.  The Battery will not have enough kick to start the car.  I will get it jumped and it runs perfectly fine.  Some times the car will start right back up after it has been running for a while, and sometimes it won't.  In reading in the Haynes manual on these different things I keep coming across the PCM.  I have pulled the battery and charged it, and I will take the car out again latter today to see what happens.  If it dies again I'll take the battery in for a load test.

Is there a way to test the PCM?

Answer
Hi Jack,
The check engine light codes are perhaps relevant:
The 21 code says that one or both of the oxygen sensors is off-value; a readout via the diagnostic plug under the dash would give a more refined ID of which sensor is bad.
The 12 code says that sometime in the past 100 ignition key uses the battery was disconnected. That probably is true because you disconnected the battery to charge it? If not, then I would check the battery clamps, and also follow the - post clamp wires to their respective ground points and check that you have clean firm grounds.
The abs light means some malfunction was found, but a separate readout of the abs controller by the under dash plug with a reader is required to find out what.
I don't see a code that would explain the battery running down. Do you get a warning light or if there is a voltage meter on the cluster does it show a low reading? If neither, then I would suspect the battery is nearing the end of its life. If you have a voltmeter check the voltage between the posts with the engine running. It should be around 14.5 volts or a bit more.
The PCM can be an issue, but your codes don't show that to be the case. So I would not attribute a possible charging problem to it.
So check the charging voltage and let me know.
You also could have a short or a hidden light that is on all the time. If you have an ammeter check what your current flow is between the battery post and a removed battery clamp (either post is OK to measure) when you have everything shut off, all doors closed, etc.
It should be less than 100mA.
Feel free to followup with info that you learn.
Roland