nytrdr24
+1y
the alternators on mazda's have an internal voltage regulator, (the little wire coming off of the back of the alternator) this runs to the ecu. so if you have put in a new one, you must have something that is causing the battery to drain down while the truck isn't running, make sure all accessories are off. as for an inline fuse, i don't know of one right off hand. there should be a fuse in the dash for the ignition, and one on the main fuse block in the engine compartment. check those, and look at your wiring harness for any nicks, or maybe a spot where it is shorting out. just my two sence, hope you find the prob.