Test the battery and alternator.
Then test the Mega(Maxi)fuse (behind the coil pack).
Per Ray, some of the reasons for a shorted megafuse. "Excessive current draw from a bad VR, or water on the fuse (leaking trunk liner), or shorted battery terminals. Also a seized/cracked alternator (as is actually pretty common!! lol) can cause the fuse to blow."
Originally posted by Ray:
Alternator
the "batt light" has nothing to do with the battery. it is actually a "charging system indicator light".
Replace the alternator, or POSSIBLY the megafuse (only thing that negates the megafuse is the off-and-on light. a megafuse would cause a steady light at all times, which you had at the END but not at the beginning.
1. Check the fuse, first (under the coilpack.. you'll see two metal posts sticking up.. measure resistance across them.. should be near 0)
2. Measure running voltage(alternator): check voltage across battery terminals while running.. should be 13.8-14.7 +- .3
3. Measure off-voltage(battery): turn off car, remove surface charge (interior and headlights on for 60 seconds)..
should be >=12.0
How-to for alternator replacement is under Duratec Maintenance FAQ
Ray
Edit. Also check the wires as suggested by Stazi. LOL. Both typing at the same time.
