I have the headlight relay wire harness from FABO member Crackedback so my headlight load comes straight off of the alternator.
During the daytime, it will idle at 13+ volts but that is with none of the load of headlights, brake lights or the A/C system. I've wondered what the chances are of me discharging the battery by extended night driving at slow speeds, like cruising.
I have a 75 Power Wagon that always shows a healthy charge when driving yet the battery loses charge after a few weeks of sitting. I have tried different batteries and the problem persists. I was told that a diode may be to blame, that an alternator can actually function normally and provide charging and still
discharge when at rest. I've pulled the positive cable when I park it and yeah...the truck starts fine after 2-3 weeks or more so something is drawing power. That truck is really basic....No A/C and I rarely drive it at night.
I have gone through numerous ECMs in the Charger. It has me curious if something in the electrical system leads to early failure. I do use a ground strap to the ECM. I replaced the underhood engine harness 11 years ago. The engine has 2 ground straps on it. This alternator is one constant though. I've had it for many years. Again, I did buy this:
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I've just delayed the swap since I've been busy with other things.