03 7.3 Bat light on, something is not shutting off
I have an 03 with a 7.3 A month ago I replaced the alternator (old one burned up) and batteries. I am assuming that my current problem burned up the old alternator. My battery light is staying on for a long time in the mornings. It will go off after 10 to 15 miles but seems like it is taking longer. I tested the alternator while idling and something was making it put out 40 amps. If I have to make several short trips it will drain the batteries/ I think maybe the glow plug circuit is staying on, does this make sense?