Ford F250 Battery Drains when the headlights and radio are used while driving. Help?
Asked by Brandon Aug 03, 2014 at 02:09 PM about the 1998 Ford F-250 3 Dr XL Extended Cab SB
Question type: Maintenance & Repair
Ford F250 XLT Triton V8. My truck will start and run fine. I had the battery and alternator tested both show positive and are working. If I turn on my headlights or my radio while driving it will drain the battery and the truck will die. Any help is appreciated!!!!! What should be my next steps to finding the issue?
5 Answers
Clean and tighten all battery cable ends. Also clean and tighten the negative battery cable where it attaches to frame and motor. Sounds like loose connection or failing alternator. Alternator putting out 14 volts?
Yes, it is putting out 14 volts. The one thing I didn't do that I just realized was turn on my lights when they where testing it. Heading to have that done now. Was actually working on checking all connections when I had that realization. Thanks!
Also check tighten and clean main positive cable to fuse panel.
So took it to an actual mechanic friend of mine. He tested the altenator under the load of the lights being on and no change in voltage. He did test the battery again and it failed. Dry Cell possibly. Changing the battery hopefully that solves the issue. Also I did what you suggested and cleaned and tightened all contacts and cables. Thanks!