Battery charging relay

Asked by Nov 05, 2014 at 10:30 AM

Question type: Maintenance & Repair

2003 F250 Super Duty.  A relay that
controls the alternator.  Where is it in
the fuse box.  I lost the book.

3 Answers


No relay per say, voltage regulator is the main control, you didn't mention your engine, but check your main fuses if it is not charging first, and do not remove a battery terminal with the engine running, you could fry a bunch of electronics. I suspect the alternator has failed just by the age of the rig. Get the battery fully charged and have the charging system checked.

Best Answer

It's a 5.4 gas engine. Alternator is less than a year old.


Was it new or a reman alternator?

Your Answer

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