New battery dead second straight morning. - Ford Forums

droosim · 03-23-2008, 12:42

I recently replaced the OEM battery in my 2003 Ranger because it was dead.
Now my new one is dead for the second straight morning.
I had gotten it tested and everything is normal, no alternator prob.
I left no lights on, door ajar, etc.
Any ideas from anyone?

droosim · 03-23-2008, 14:14

I don't know how,
but I think I've narrowed it down to the AC clutch.
With the AC on or off the compressor runs.

thefonz · 03-24-2008, 09:30

From what you are telling us, I don't think that is your problem. How have you verified battery condition and charging condition. The compressor running should have no effect on the alt. putting out enough to charge the battery

droosim · 03-24-2008, 10:21

I've tested the battery myself, and had it tested professionaly,
both results were normal.

When I test the battery while the truck is off,
the voltage is somewhat low, multiple times tested between 6 and 11 volts.

I have also disconnected the battery as soon as i turn the engine off,
tested it, and it read 11 to 12 volts.

That is how I have verified battery and charging condition.

Lastnight I left the negative connector off,
and this morning, after reconnecting it,
it started with no problem.

Sorry for not being specific in the original post.

thefonz · 03-24-2008, 12:27

Engine off, battery voltage should be about 12.5 volts. Engine running and accessories on, tester across battery terminals should be 13.5-14.5 volts to be enough to charge the battery. If you are getting 6-11 volts, (engine off) you either have a bad connection or bad battery. Best test for battery condition is to be load tested.