Colleague in Huntington , WV having issues. 2000 Dodge Ram 1500 cargo van, automatic v-6 two wheel drive.

QUOTE
Battery is new. Had 2 different parts houses check battery and alternator they checked out fine. Up until today it would run fine during the day. At night when headlights on I would only have about an hour then heater will quit then panel lights flashing and dimming and headlights will go totally out then van will die. You can get a jump and it will crank right up.
Today with engine running I removed negative cable and engine died. Now it will not start. Checked and cleaned battery terminals. Going to get it jump started and see after charging if it will start.

First off dont try disconnecting the battery cable while the van is running to see if it is charging. That worked in the old days but you run the risk of screwing something up on your computer controlled vehicle. Fist thing to do is to check for power a the large batt cable on the back of the alternator.It should have battery power at all times. Possible blown fuse in PDC if there is no power there. If all is ok there you will either have a single plug with 2 wires in it or 2 studs on the back of the alternator to connect the field wires. Should be a blue and a green wire usually. The blue wire should have 12 volts when the key is on. The PCM duty cycles the green wire to ground to regualte the charging. With a test light hooked to the + cable it should be illuminating the test light when touching the green lead. If not, you may have a broken wire or a faulty pcm.

the vr is part of the ecm.
it is not uncommon for them to go bad and rather than replace the ecm, wire in a 70's era voltage reg.
this will be far cheaper.

while you said you tested the batt and alt, did you drive it in and have them verify it is charging in the van? that would tell you if the vr is working or not.

or if you have a meter, you might give the voltage a check while running.

He says truck wont start with jump now????

sounds like a bad alternator