blackout for a black 2017 fusion energi

[AlexMo]

I totally drained the battery by leaving the lights on. I was so used to my 2015 Subaru that automatically killed lights when keyed off or just left for a few minutes, that I assumed the Fusion worked the same way -- WRONG! Then found out how to put a jumper a terminal on the left side of the engine compartment, and get it started. Then (stupidly/ignorantly) without driving it, locked the car and took off for 3 days. When I got back, I was locked out of a dead car! Then found out about the plastic snap over the door handle, hiding the keyhole. Got her started, rode around for 15-20 miles, took it to the dealer, and noticed the lights were still on. If you leave the lights on manual (one click to the left of the auto position, far right side of the dial) overnight, consider your "starting" battery dead. Yes, even if you lock the car from outside. Yes, even if you charge with the external L2 port for numerous hours. Lesson learned: the high-voltage (plug-in) battery *and* the medium-voltage hybrid battery will not "donate" juice to the main battery (located inconveniently in the now-inaccessible trunk, with the jump terminal in the now-inaccessible engine compartment).

 

Also ... dealer mentioned:

• replacing the 12V battery was "no small deal" due to the tight fit in the trunk with the plug-in batteries controlling space .. anyone done it?
• the 12V supplied by the factory often went south after ~3 years (age of mine) ... anyone seen that? 

 

So why does a car smart enough to connect to my wi-fi also dumb enough to drain the master battery when lights are left in manual on?

 

See attached a photo proving I could get a bag of clubs and a pull-cart in the Energi trunk, my 12V battery is located behind the near left wheel of the cart.

 

[murphy]

Attach a small rope to the emergency trunk release handle and feed the other end up behind the right rear fold down seat back. 

I tied that end to the seat back latch bar so it would stay in place.

I don't understand your inaccessible engine compartment statement.  Open the driver's door with the key hidden in the back of the fob.  Pull the handle to release the hood.

 

If you drive your car every day you won't have a problem with the 12 volt battery.

If you drive it once a week, like I do, keep a battery charger handy to keep it charged. 

There are lots of microprocessors in the car that are never turned off.  That is what drains the battery. 

A Tesla uses the big battery to keep the 12 volt battery charged.  It takes longer but you can end up with both batteries dead. 

I have a jumper pack in the trunk to jump the 12 volt battery if necessary.

 

I also replaced the OEM wet cell lead acid battery with an AGM battery.

[AlexMo]

Right you are, Murphy, I was kinda documenting my "learning process" (couldn't find the keyhole till I called the dealer).  Understand about all the vampire equipment, the real puzzler for me is that there is no auto-shutdown for anything as big of a drainer as the headlights. Almost all car manufacturers have some sort of time delay for lights-out these days, no? 

 

Tesla engineering may have been copied by Ford in some respects, but since the Fusion line is discontinued, I can't see a "Suggestion Box" existing anywhere ? so I'll just have to learn from my mistakes, and triple check the lights are never left in manual-on position. When I point the fob at the car and say "All Off" I'll have to remember that means everything except the headlights.... and I do drive it 2-3x per week, so doubt the dealer's estimate of 3-year battery life. 

 

Still would like to hear if anyone has attempted a replacement themselves, does seem to be a lot of thin-wall padded material in the trunk to take loose first.

[murphy]

I have replaced my 12 volt battery. Several christmas tree style clips have to be removed.  If you break one they are available at Lowe's in the nuts and bolts department.  The fiber panel in front of the battery will have to be folded out of the way to get access to the battery.

 

I will have to test the headlights..  The 12 volt power sockets turn off 70 minutes after the car is turned off.  I don't drive after dark much anymore so my headlights are very seldom on.

 

Somewhere on this forum is my detailed description of what it took to replace the OEM 12 volt battery with an AGM battery without losing the learned engine parameters.  It was a "hot" swap.  I am an Electrical Engineer so I knew what I was doing.  Things like insulating the + battery lead since it remained hot through out the process.

[murphy]

I tested the headlights.  If the control is set to auto the timeout delay can be set to 0, 10 , 20 etc seconds.

If the control is set to on there does not appear to be a timeout.  However as soon as I opened the door a chime started to warn that something had been forgotten.

 

[jsamp]

Alex,

 

I recently hot swapped my 12V battery as well.  If you remove the entire fiber panel (not just the battery door) it is very easy to replace.  There is a thread on here with a suggestion for an AGM battery that actually fits in the existing battery tray without modification, though the + and - terminals are switched.  I just used the standard lead-acid from Ford.  The standard battery has a 3 year warranty, so you got what was expected from it.

 

On 9/21/2020 at 4:34 PM, AlexMo said:

 Lesson learned: the high-voltage (plug-in) battery *and* the medium-voltage hybrid battery will not "donate" juice to the main battery (located inconveniently in the now-inaccessible trunk, with the jump terminal in the now-inaccessible engine compartment).

 

 

BTW: there is only 1 HVB in the car, no "Medium Voltage Battery".  The 'hybrid battery' is merely a computer limited portion of the HVB.

Edited September 24, 2020 at 05:05 AM by jsamp
added quote

[jj2me]

On 9/22/2020 at 9:53 PM, jsamp said:

There is a thread on here with a suggestion for an AGM battery that actually fits in the existing battery tray without modification, though the + and - terminals are switched.

 

https://www.fordfusionenergiforum.com/topic/4751-2017-fusion-energi-dead-battery-issues/?do=findComment&comment=33150

 

[AlexMo]

This is great info, all! It makes sense that Ford wanted to protect the many laboriously inputted settings (WiFi password, door codes, charging schedule, etc.), so you can't drain all batteries at once a la Tesla. But why the HVB can't "assist" with starting is not so clear; I noticed that when the starting battery is dead, I could no longer charge through the L2 port either. My battery is still in good shape after the full discharge, and I use about an 80/20 mix typically of EV/ICE. So something is sending charge to the 12V battery even when the ICE isn't turning/charging, right? Therefore, how can the 12V battery get 100% discharged while the HVB is 100% charged? Maybe one of the EEs here can 'splain that to me.

 

Really a headscratcher too that I can lock the car and it will leave the headlights burning, so I guess it's a slight engineering oversight, and I'll consider it part of the learning process. The "you left your lights on" chime is a bit subtle, not rapid and annoying like my 99 Dodge Ram pickup, so that may be an engineering/useability testing oversight as well.

 

I guess every car has its quirks, and the later, high-tech models have plenty, I'm sure. Still really love this car, EV mode gets me to most destinations and I've used about 100 gallons of gas since buying the car used in April 2019. Our climate is pretty mild in nearly coastal Oregon too, which is probably why the battery is still in good shape. It is good to know that a hot swap is needed to change the battery out when it does die. 

 

Will I get longer life out of an AGM battery? I know they're used in aircraft and some marine applications where you don't want the possibility of acid leakage due to inversion or dramatic departure from level. Sounds like the reverse terminal thing could be an annoyance in the cramped space of the Energi trunk.

 

[murphy]

The HVB can only charge the 12 volt battery when its contactors are pulled in to connect it to the car.  Guess what pulls in the contactors.  The 12 volt battery is the answer.

 

Tesla does keep the 12 volt battery charged from the HVB.  4 or 5 times a day, when the car is parked, the 12 volt battery gets charged.  The result is what is known as vampire drain.  People are endlessly complaining that their car lost x number of miles over night.  The Energi HVB is too small to do this without causing a huge fuss about lost miles.

 

An AGM battery's voltage stays good to a much lower charge level than a wet cell battery does.  It will still pull in the contactors when it is very close to being discharged.  A wet cell battery can't do that.  The wet cell battery in my backup generator is changed every three years.