Guys I had the check engine light come on, so I pulled over and checked the codes.

41 came up and I have determined it is a charging related code.

Checked my connections, and all look good.

Symptoms:

When the check light came on, I scanned the gauges, everything looked OK. The volt meter was siting at 1/2 gauge, straight up, not in a charge, but not discharge.

As I exited the interstate, the volt gauge dropped, to a about 1/4 gauge, a fairly good discharge reading. If I bring the RPM up, the gauge would swing over to a charge (over half gauge) reading.

As I drove through the 35mph zone, it would stay on a discharge reading, but if I goosed it, it would again swing to charge.

When I parked, and went to N (no load on the engine/trans) the gauge would go to the middle at idle. If I slipped back into gear (Put the load back on the engine) it would again drop.

If i turned on headlights, during idle, no noticeable drop in volts was seen.

In my opinion the swinging of the gauge to the charge side is saying the alternator is working, my conclusion may be a faulty battery?

I have noticed that over the past two months when I was unable to drive the truck that the battery would discharge if I let it set for 5 or so days.

I would charge it up, and start the truck about once a week, and the battery would not seem to hold a charge without the aid of at least a 2A trickle charge.

What are your thoughts? I really need to get this fixed before I have to travel home tonight and need the headlights.

Truck is a 1993 Dodge W250 Diesel. So one good thing is the battery wont drain too quickly while running. All i really need to have is power enough to hold the fuel shutoff valve open. The diesel doesn't have any ignition draw.

P 41 code is normally an oxygen censor code. I do not have my OBD 11 with me or any other code books for OBD 1 with me also. Since you have found the code I believe your truck runs OBD 1?

Have the battery load checked at the parts store. It's free.

i checked the codes 3 times for verification. I always do this to catch errors.

my actual codes are:

12 - 41 - 24 - 55

12 = battery disconnected recently (makes sense because it just left the repair shop Friday)

41 = Alternator field or charging issue

24 = bad TPS signal (makes sense because I have no TPS hooked up, instead I run a potentiometer)

55 = End of codes

Alternator is about 3 years old, was a new not rebuilt unit.

Battery is also 3 or so years old.

so it is either the alt or vr?
is the vr part of the computer that year?

can you check for voltages to the field wires on the alt?

if it is part of the computer, the older style vr are pretty stand alone and you can bypass the original pretty quick. use the 1 field vr electronic type. most places only carry the electronic type. is easier to rewire to me, and doesn't require a special plug.

Since it is OBD 1 it is a generator field code not an Oxygen censor like I stated above. That could mean a few things.Look at ASD relay,alternator conectors,wiring,fuses and the battery.

Everything before 1996 is OBD1 and a few vehicles in 1996 were still OBD1.

John, 1995 Neons are not fully compliant OBD11 Systems. This is one reason I have never owned a pre 1996 Neon. By January 1,1996 every vehicle sold in North American was to have the OBD 11 System in the Vehicle. This is why I say that there still could be a 1996 Vehicle built before January 1, 1996 with the Non fully compliant system. I would think that Chrysler would of gone to the Full OBD 11 System with the start of production of 1996 vehicles.

Diesel charging issue. Let's keep the OBD stuff out of the way for the guy...

As said, make sure you have good battery connections, alt connections and check the feed wire on the alt. If you can't find anything on the visual, time to get a voltmeter and check the battery(s) and the alt output.
Thos old trucks tend to have cruddy connections after this much time and miles, so a good look/clean can often fix stuff.

You need to check the alt amps output and the battery voltage while checking the amp output. That will tell you alot. If amps and volts are way to low then go to the field wire on the back of the alt that goes to the PCM and ground it to see if it gets full output. If it dont put out like that then check the voltages to the field wires and see if it has 12 or more on the 12 volt field wire. Ron

Alternator was bad. Thanks for the help!