I recently changed the spark plugs in my '11 screw FX4 and in doing so, I disconnected the negative battery cable. Apparently, this activated the battery saving system (BMS) which affects how some of the accessories work. I read about this deal in the manual and on this forum and learned that the truck needed 8 hrs. of "sleep" time to reset the system. I've done that but still have the issue. I took the truck to my local Ford service dept. thinking that there may be a way for them to reset the system. When explaining the situation to them, they looked at me like I had 2 heads. They didn't know anything about a BMS system and certainly knew of no way to do a reset. The battery tested low so we installed a new one. The service dept. manager did some research on his computer and did learn that there was such a system so I did regain some credibility. We decided that the old battery being weak may have been the issue and that we would give the system a chance to reset itself with the new one. All that was yesterday. This morning I'm still getting the message on the info screen that the system is in "battery saving mode". Oh, they did clear any codes that were there yesterday. Any ideas or suggestions? I'm supposed to return to the service dept. if I still have the problem, but I don't have much confidence in them knowing what to do next.

 

Try charging the battery over night, remove both cables first. then put on a charger.
As I understand, that is basically saying your battery in undercharged. This mode is trying to protect the battery, so there is enough power to run the truck when you start it.
These new trucks use a lot of energy, and if you do only short trips here and there it isnt getting a full charge.
Just what was explained to me once
I have purchased new batteries that were low before. I always charge a new battery before I use it
After charging and you still get the same message, you may have a charging issue.

 

There's a known issue where in the BCM requires reprogramming to the latest calibration level, I have performed this operation on my truck.

Tell the goobers to run an OASIS REPORT with your symptoms and it will give them instructions on what to do. Or preferably take it to a dealer that has a tech with at least half a brain.


P.S. They also have the ability to do a BMS reset using IDS.
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Thanks, guys.