3 replies to this topic

[zone1090]

Had car towed in to shop with dead car. I have installed a new battery about a month ago. Old battery tested good though.
After reading page after page of people with this problem I have never seen what anyone did to fix it.

[Plus 3 Golfer]

The Ford "fixes" were several CSPs /TSBs that you've likely had done.  I don't recall all of them but after the last Ford CSP 15b04, the reports of dead batteries / no start declined significantly.  I note that 15b04 expired in May 2016.

 

My guess is you have an intermittent, abnormal low or high resistance in wiring / connectors / modules / sensors that prevent certain modules from going to "sleep" when the car is off.  After so many hours, the "awake" modules drain the 12V battery to a SOC insufficent for the modules to operate (voltage is too low) when trying to start the car. 

 

Some of those with the "dead battery" issue had specific modules replaced and one had the module that attaches to the battery post replaced (can't recall the name, but it has a fuse and metering sensors for the 12V battery monitoring algorithm).  My guess in these "rare" instances where the dealer found a specific cause, the conditon was a "hard" failure which a good tech could isolate.  But, intermittent issues are very difficult to isolate as there are likely no DTCs stored and are virtually impossible to troubleshoot when the modules are active and the abnormal condition doesn't exist.  

 

I assume the "lemon law" in your state is no longer applicable to your car.  

[obob]

When I was having that problem before the "fix" I bought something like this which gave me confidence I was not going to be stuck somewhere.  With 4 dead batteries episodes I have a flavor of your experience.  

 

https://www.amazon.c... jumper starter

 

It might even be cheaper on black friday and there are lots of companies selling them.  (The one I linked is an "Amazon's choice" )

[zone1090]

After the first time (6months old) I bought and taught everyone how to use jump pack. Good thing because it has broke down with everyone.
Dealer tried to blame new battery until they found out I am in the battery business over 30 years. Last time they said battery was bad so I checked it myself and it still tested good on Midtronics tester. I changed it anyway.
Dealer managed to repower car and can't find any drains. So looks like we will bevdealing with
another session