HYBRID 12V Battery Mystery SOLVED

[Mavster Mechanic]

Regarding LED life- that's an often cited false narrative.

LED may last 30,000 hours if you turn them on one time, and leave them on, at consistent voltage; in a stationary climate controlled laboratory.

One third of theoretical hours are realistic in real life. But still longer life than anything else. So 10,000 hours is still pretty good.

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[Ryom]

Holy crap that's amazingly dumb! An entire team of engineers designed that, there must have been a reason for this as a specification.

I need to dig up my old 12v power socket test thingamabob and see if the '26 does this.

https://www.amazon.com/dp/B00SXZDKTW

I have one that displays inside temp and voltage. Could be useful for folks that want to keep an eye on their battery.

 

[pigsareus]

Some of you will laugh.
Some of you will cry.
Some of you will say "Holy Crap that's amazing!"
Some of you will say "Holy Crap that's dumb."

Here goes.

Fact: 2022 Hybrid (and others) actively drain a 12 volt battery to the computed 80% charge level.
Then do not try to add charge to the 12 volt battery until a computed 60% or lower charge is reached. God only knows why.
For 3.5 years my 12v battery has been "maintained" at about 60% charged. Always a resting voltage of 12.1 or 12.2.

Fact: running your headlamps will force the 12v battery to be 100% charged given enough time. (DRL will not do it. Parking Lamps only will do it.)

Fact: running your vents blower at speed 6 or 7 will force the 12v battery to be charged to 100% given enough time.

Fact: attaching a trailer, 4-pin or 7-pin will force charge the 12v battery to 100%.

Theory A: the truck needed to detect 12 volt demand, and above a certain wattage to trigger 12 volt charging.

Why would fan level 6 trigger battery recharging and fan level 5 would not? Why would full headlamps trigger battery recharging, but DRL would not?
Did the truck detect demand to run my camper fridge and coach battery?

I tested this last part. From Amazon I ordered a $10 LED brake light for the 2" hitch receiver with 4-pin connector.
Wow! The LED brake light pulling no power when not braking, and only 4 or 5 watts when braking DOES TRIGGER 12 volt battery recharging to 100%.
It's not the electrical demand that triggers recharging. It is simply thinking a trailer is there that triggers recharging.

Theory A shot down.

But this explains a lot.
This explains why some people have more 12v battery issues than others.

Those that drive at night a lot have more battery charging by happenstance.

Those that use fan speed 6 or 7 have more battery charging by happenstance.

Those who connect trailer wiring (and you don't even need a trailer!) have more battery charging.

Not a permanent fix. But a work around. Some of you may prefer running your headlamps more often over plugging into a home charger.

My 12v battery has been 100% for ten days in a row now. And is maintained at 12.7 or 12.8 volts. But I need to do one of the three "triggers" above or it rapidly starts to declin
More to come...

I'm an old guy who seldom drives at night, doesn't even have a trailer hitch, and doesn't like having the vent on high and over 3 years I've never had any battery problem with my '22 xl hybrid.

 

[MakinDoForNow]

Perhaps the easy answer is to put a voltage monitor into cig/power port and turn on enough electrical to keep buss at 14.7-14.8+!!?

 

[Glen Baker LLC]

Perhaps the easy answer is to put a voltage monitor into cig/power port and turn on enough electrical to keep buss at 14.7-14.8+!!?

I had one plugged in last night and I noticed, when the headlights turned on the voltage ramped up 14.7.

 

[okgaz]

I tested this last part. From Amazon I ordered a $10 LED brake light for the 2" hitch receiver with 4-pin connector.
Wow! The LED brake light pulling no power when not braking, and only 4 or 5 watts when braking DOES TRIGGER 12 volt battery recharging to 100%.
It's not the electrical demand that triggers recharging. It is simply thinking a trailer is there that triggers recharging.

Am I reading correctly that you have a little LED brake light attached and that does it? Link?

 

[Glen Baker LLC]

Am I reading correctly that you have a little LED brake light attached and that does it? Link?

On some year Mavericks plugging in that trailer hitch brake light will disable the
Backup Cross traffic alert and
Blind Spot Information System (BLIS). Check out post #29

 

[okgaz]

Before warned on some year Mavericks plugging in that trailer hitch brake light will disable the
Backup Cross traffic alert and
Blind Spot Information System (BLIS). Check out post #29

Good information.

Specific trims or years? Or just been noted on some trucks and not others?

 

[Glen Baker LLC]

Good information.

Specific trims or years? Or just been noted on some trucks and not others?

What year is your Maverick and do you have blind spot monitoring and backup cross traffic alert?

 

[DWV]

Some of you will laugh.
Some of you will cry.
Some of you will say "Holy Crap that's amazing!"
Some of you will say "Holy Crap that's dumb."

Here goes.

Fact: 2022 Hybrid (and others) actively drain a 12 volt battery to the computed 80% charge level.
Then do not try to add charge to the 12 volt battery until a computed 60% or lower charge is reached. God only knows why.
For 3.5 years my 12v battery has been "maintained" at about 60% charged. Always a resting voltage of 12.1 or 12.2.

Fact: running your headlamps will force the 12v battery to be 100% charged given enough time. (DRL will not do it. Parking Lamps only will do it.)

Fact: running your vents blower at speed 6 or 7 will force the 12v battery to be charged to 100% given enough time.

Fact: attaching a trailer, 4-pin or 7-pin will force charge the 12v battery to 100%.

Theory A: the truck needed to detect 12 volt demand, and above a certain wattage to trigger 12 volt charging.

Why would fan level 6 trigger battery recharging and fan level 5 would not? Why would full headlamps trigger battery recharging, but DRL would not?
Did the truck detect demand to run my camper fridge and coach battery?

I tested this last part. From Amazon I ordered a $10 LED brake light for the 2" hitch receiver with 4-pin connector.
Wow! The LED brake light pulling no power when not braking, and only 4 or 5 watts when braking DOES TRIGGER 12 volt battery recharging to 100%.
It's not the electrical demand that triggers recharging. It is simply thinking a trailer is there that triggers recharging.

Theory A shot down.

But this explains a lot.
This explains why some people have more 12v battery issues than others.

Those that drive at night a lot have more battery charging by happenstance.

Those that use fan speed 6 or 7 have more battery charging by happenstance.

Those who connect trailer wiring (and you don't even need a trailer!) have more battery charging.

Not a permanent fix. But a work around. Some of you may prefer running your headlamps more often over plugging into a home charger.

My 12v battery has been 100% for ten days in a row now. And is maintained at 12.7 or 12.8 volts. But I need to do one of the three "triggers" above or it rapidly starts to decline.

More to come...

I don't drive much at night, but I did notice on one long 200 mile drive with headlamps on, that the battery charged to about 96%

I don't understand why, but when I replaced my flooded battery proactivly with an AGM H4; the normal 80% charge for the flooded batteru increased to 91% for the agm. No change other than the BCM reset and overnight relearn.

Someday I will try to increase the charge level via Forscan, but I just can seem to get "around tuit"!

 

[catrikejoe]

You do know if look in Forscan settings max charge is around 80% .
There are people changing that to 100% fixing the notification issues low battery.

 

[okgaz]

What year is your Maverick and do you have blind spot monitoring and backup cross traffic alert?

See side bar. 2024 Hybrid XL - I do not believe so, as I have the base trim. I obviously have the standard lights on the side mirrors and alert on possible collision (but do not think that's what you are talking about).

 

[Glen Baker LLC]

See side bar. 2024 Hybrid XL - I do not believe so, as I have the base trim. I obviously have the standard lights on the side mirrors and alert on possible collision (but do not think that's what you are talking about).

Does your driver's side mirror look similar to this?

 

[okgaz]

Does your driver's side mirror look similar to this?

Nope. Just a plain old mirror. In fact, it's manual - have to stick my hand out the window to adjust!

 

[Glen Baker LLC]

Nope. Just a plain old mirror. In fact, it's manual - have to stick my hand out the window to adjust!

Ok.
Do you have this light?
If you do, you have BLIS Blind Lane information system. That will be disabled if you plug in the trailer hitch brake light and you will get the dashboard warnings as shown in the above photos.

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