So it's been a while since I've had a major issue with my 2011 F150 with the 5.0. I just made 96K. In October during a cold snap my factory battery died. I replaced it with a duralast gold battery. Now I'll be the first to say that MOST duralast products are terrible. I used to sale them afterall. But I've ALWAYS had great luck with the duralast gold batteries. Anyhow, I had no issues until two weeks ago . Leaving my house my battery light came on. After a few miles it went off. Then for another few days the battery light would come on more often. I checked my connections and decided to swap out the battery, hoping it wasn't my alternator. Changed it out, used my truck for a few days and no more battery light. I got in my truck and left work tonight and my battery light came on once again. After about 5 miles of travel it went off. I have no weak starts, my lights aren't dimming, and nothing seems to be amiss. Tomorrow I'll put a load tester on it. Anybody know how many volts the alternator should be putting out? I would think 13-14. If it turns out to be an alternator, any suggestions of a replacement? I prefer a new to a rebuilt. Thanks for the help in advance.

 

Mine puts out about 13.6-13.7 volts cruising on the highway. If you're not aware, these newer trucks cycle the alternator based on electrical demand, so you may have to watch for a bump in voltage when the alternator kicks on.

With that said, do you have any aftermarket electrical components wired in? If you ground anything directly to the negative battery terminal, you bypass the Hall sensor and the computer will not charge your battery correctly. This seems to be a common problem with people who don't ground their lights and what not to the chassis.

 

Did you have the battery reset? I have a scanner from Pepboys that will reset the battery

 

How do you reset a battery?

 

The battery will relearn its state of charge after the vehicle has been off for 8 consecutive hours (just as long as haven't bypassed the Hall sensor like I explained in my first post). I don't believe you need to manually reset the battery unless the truck is not getting 8 consecutive hours of "sleep".

From the Ford Manual:

Battery Management System (If Equipped)

The battery management system (BMS) monitors battery conditions
and takes actions to extend battery life. If excessive battery drain is
detected, the system may temporarily disable certain electrical features
to protect the battery. Those electrical accessories affected include the
rear defrost, heated/cooled seats, climate control fan, heated steering
wheel, audio and navigation system. A message may be shown in the
information displays to alert the driver that battery protection actions
are active. These messages are only for notification that an action is
taking place, and not intended to indicate an electrical problem or that
the battery requires replacement.

Electrical accessory installation
To ensure proper operation of the BMS, any electrical devices that are
added to the vehicle should not have their ground connection made
directly at the negative battery post. A connection at the negative
battery post can cause inaccurate measurements of the battery
condition and potential incorrect system operation.

Note: Electrical or electronic accessories added to the vehicle by the
dealer or the owner may adversely affect battery performance and
durability, and may also affect the performance of other electrical
systems in the vehicle.

When a battery replacement is required, the battery should only be
replaced with a Ford recommended replacement battery which matches
the electrical requirements of the vehicle. After battery replacement,
or in some cases after charging the battery with the external charger,
the BMS requires eight hours of vehicle sleep time (key off with doors
closed) to relearn the new battery state of charge. Prior to relearning the
state of charge, the BMS may disable electrical features (to protect the
battery) earlier than normal.

 

battery system management or something like that not the actual battery.
sorry

 

I installed a 12,000lb winch on my 2011. The winch installation guide said to connect the positive and negative cables to the battery. Based on posts in this thread, should I move the negative cable to the frame instead of the battery to assure proper alternator function when the winch is in use?

Thanks

 

Don't quote me on this, but your winch probably assumes that most people have a pretty dinky ground wire from the frame to the battery, which is why its saying to simply ground to the battery. If you are worried about grounding it to the frame, but still want the BMS to be accurate, you could splice the winch ground wire into the battery ground wire before the Hall sensor. I don't seeing this being a huge issue with a winch compared to something that draws current consistently.

 

Thanks for the replies. I HATE THIS TRUCK. But it's nearly paid off so I'll just suffer with its bull crap.

 

alternator, wife's 05 expedition did this dealer replaced alt.