2004 Dodge Ram 6 cyl Two Wheel Drive Automatic 92000 miles
I have dodge diesel 3500. Battery dies after 3 days of sitting. Replaced w/2new battery's no improvement. When I first crank up the truck amp gauge showing a load about a 13volts after couple mins, of runing. Alternator goes to no load at 14+ volts. I thought it was voltage regulator at this point, so I changed alternator. Same problems. Shows load and goes to no loads. Battery Still dies.
The only none factory item on the truck is extra fuel tank which has 12volt switch over. I just want to mention this so you'll have all the info.
Appreciated very much for your help. Thanks, Herb
Hi herb duncker. Welcome to the forum. The voltage regulator lives in the Engine Computer, not the alternator, but regardless of its location, it is working properly. What you are seeing is it working to recharge the batteries after they've drained excessively. Many years ago we would remove the battery negative cable and insert an ammeter to measure the drain, but that no longer works because it takes up to 20 minutes for some computers to go to " sleep mode". During that time it is common for them to draw very high current that would damage most meters or blow internal fuses in digital meters.
Instead, you will have to remove fuses to see which circuit(s) are draining the battery. To kill them in three days requires a pretty substantial draw. That can be measured with test equipment with an inductive pickup that can be placed around one of the main battery cables.
In particular, suspect the Central Timer Module (CTM) is not turning off. That's the counterpart to Ford's very troublesome Generic Electronic Module (GEM).