83-88T-Bird Guy

I tried that last night.

Absolutely no load draw at all and undisturbed for over 8 hours.
I even hooked up a 3 amp charger/maintainer to keep the voltage up close to 13 V and wired like Ford says ( ground to the fender)

It did not work for me.

Spiky

I haven't checked the voltage, but I unplugged mine earlier this winter and have had zero warnings since. And we just went through a very cold January, much colder than back in November when I got the warning a couple times with it still connected.

Feathermerchant

Undisturbed means no loads, no charging. By connecting the 3A charger you kept the system from calculating the battery charge state.

The donut sensor on the battery negative lead is used to measure the electrical current entering and leaving the battery. With the charger connected the system cannot measure the battery charge state to reset itself. Undisturbed means what it implies.

Spiky

You all realize that many trucks are being re-learned every night. There's no button to push, so it just is constantly paying attention to the charge level. For instance, I am usually done driving at night by 9pm, and don't leave until 7.

83-88T-Bird Guy

Yeah, I had a brain fart when I was reading the Ford manual. I kept thinking the sensor had to see 13V all the time.

Tonight I will fully charge the battery again then disconnect before I start the 8 hour test.

beaker80

OBD scanners/reader ports are not powered unless the key is in the on position. I run an ODBII scanner all the time and that port powers off before the radio does. I was having the same battery issues as everyone else. I even replaced the original battery after 5 years. This winter I was again getting the "Low Battery" issues. I have disconnected my Hall sensor and will not reconnect it. My charging voltage at the OBD port is 14.1 - 14.2 constantly. I have no issues with this. I used to have to have a trickle charger constantly on my battery when it's cold out (-10 to -25 Celsius).

jon_l

@beaker80 - is “Hall” sensor the same neg. cable “donut” sensor described in recent posts?

beaker80

Yes it is.

compleckz

Hello all,
Bringing this thread back from a year ago. I've had my 2011 for just about 2 years, I've had intermittent keyfob issues the whole time, and I've figured out it only happens after 12+ hours of sitting. If I touch the door keypad once, the keyfob works again. If I unlock manually and open the door, the keyfob works. So it seems like the truck is "sleeping", and those 2 things "wakes" it. I started looking into the Battery Saver Mode, because I've had it come on while having the truck off, and using the radio while camping, and thought this might be a culprit.

Not-so-coincidentally, a week ago I started getting the Battery Saver Mode message pop up on the radio when I turn the truck off, after a 2 hour trip or a 15 minute trip. I've had no dead batteries or slow cranks until a month ago, the battery was just dead and would not hold a charge. Replaced the Motorcraft with another HD Motorcraft with more CCA, all has been well other than the keyfob connectivity has gotten worse since. It now won't work almost every time the truck sits 12+ hours. I'm going to start monitoring voltage closely with Torque, and try to take the ring off the negative cable lots of you have talked about.

I cannot believe there has not been any sure thing fixes after 8 years. My Park sensor for the shifter seems fine, the P lights up. My ignition tumbler is very touchy and wobbly, with the key off if I jiggle it the dash lights flicker like crazy, but I have never gone out at night and found them on-- but this is on my radar. I have also stopped leaving my cell charger/dash camera/obd dongle plugged in.

What I don't understand is how this issue occurred for lots of you from day 1, and my truck only now, years later is starting with it.

Spiky

Your ignition cylinder is broken. It isn't "wobbly", it's broken. Issues with electronic or mechanical devices can happen at any time.