12 volt battery indication - issue?

[B177y]

There is no reason to use accessory mode. At least I haven’t found one. Most EVs have no such thing.

ForScan and FDRS are the only reasons you need to use accessory mode.

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[Heliian]

ForScan and FDRS are the only reasons you need to use accessory mode.

Or when you want power on but the drive system disabled.

Theres lots of reasons for it.

 

[bmwhitetx]

you sure about that? I ask because of all the battery issues (12v) on them.

On my 24 Flash, accessory mode charges the 12v. The red battery indicator stays on in accessory mode even though it’s charging the 12v.

For "Those who got an update" the operation might now allow accessory mode LVB charging / maintenance ................ IF you got the update on "OLD" Lightnings or that it's baked into the newest model years.

I'd like to see proof by model year, with & without the modified software.

For sure my 22 used to not enable the HVB in ACC mode. You could tell because CarScanner showed DC-DC disabled, and the A/C would blow warm air (A/C is powered by HVB). You could also watch the 12V SOC slowly go down.

But some update changed this, at least for me. Now when I turn on ACC mode, I get slightly cooler air and CarScanner shows the DC-DC enabled and the 12V battery as charging at 13.5+ volts. I suspect at some point all models of a certain build came with this behavior from the factory.

OTA's use to fail; because of poor 12V but that is rare now. So some update changed the behavior. If Ford wrote decent release notes, we would know which one.

 

[Kansan]

For "Those who got an update" the operation might now allow accessory mode LVB charging / maintenance ................ IF you got the update on "OLD" Lightnings or that it's baked into the newest model years.

I'd like to see proof by model year, with & without the modified software.

I never noticed my truck behaving differently, but it could have been an update that changed the Accessory Mode charging behavior.

Here’s with the truck on:

And here’s in accessory mode:

 

[HOTAS]

I fully understand both of those. But that is not a "problem" as would be indicated by the dash light indication. As I said at the beginning, I recall reading here that what is normal is that at boot up the indication will display and it SHOULD then go out unless the 12V battery is in trouble. Mine never goes out while in accessory mode. Works fine when "On" and therefore the HVB is providing charge to the 12V system.

Guess I will ignore it.

Don’t ignore it, it’s telling you something just Like a regular car.
And the truck ain‘t “booted up“ yet, until she is in “READY“ mode.

The 12v battery Indicator being displayed is only a problem if it’s
still displayed when the “ready” light is on.

This is no different than a regular car.
When an ordinary car is in AcC mode, without the engine running (no alternator charging output), the 12v battery light is on to let you know you’re draining the 12v battery. Normal. This is what you’re seeing.
&
If the 12v battery light is still on when the engine /alternator IS running, that is a battery or charge fault indication. PROBLEM.

In our truck the “ready” light is an indication of “engine running/alternator charging“, (but in this truck the so called alternator is a dc/dc converter )
So,
If the 12v battery light is on when the “ready” light is on, there is something wrong with the 12v battery or charging curcuit. PROBLEM.

Otherwise, you’re in AcC mode and depleting your 12v battery so the 12v battery indicator you see is normal.

That said, I know it is written that in AcC mode the 12v battery is “maintained”, but that is not applicable here.

 

[TaxmanHog]

2022 Lightning Lariat ER, with the majority of OTA's applied, some still lacking....

Ignition status--Voltage-- Bat Lamp
OFF------------12.0v------not showing
ACC -----------13.4v------RED
READY---------14.5v------not showing

As mentioned by a few folks above, the battery get's moderate sustenance in accessory mode even though the legacy lamp behaviour persists, this mild boost in charging might be 'just enough' energy to maintain the 12v battery without extraordinary loads.

 

[HOTAS]

The “READY” light is a very important and very misunderstood indicator in Hybrid/PHEV/EV’s.

It means the “engine” is running and ready to be “driven”.
since we can’t see, hear, feel or smell that anymore, it’s an important indicator to understand. Its differentiates AcC mode from the vehicle being fully “on”

 

[HOTAS]

On a side note, I was talking to a lady at the optometrist who drives a new sleek Prius. I asked her how she likes it. (I’ve had 2, years ago)
She said she was having trouble with the car not starting, needing to be jumped and the 12v battery being replaced repeatedly. (Like it’s the car’s fault and a flawed car). Hmm, tell me more….

Said she likes to listen to the radio with the car off, like she did in her previous cars, while her kids are playing sports.
I said well, the radio shuts off after 5 minutes or so (to protect the battery), doesn’t it?
She said yeah, but I just turn it back on. (Ughhh!)

i explained that if she wanted to listed to the radio for longer periods of time to keep the Prius in “Ready” mode. It would keep the 12v battery charged.
She acted like that was gonna somehow be wrong. Like waste energy or something, lol.
In fact it’s the exact thing to do.

She’s so used to having an enormous 12v battery with like 900 CCA (amps), the radio could play for days. She doesn’t understand these new tiny 12v batteries are only meant to boot up a larger 12v system.
Again ignorance gives great Hybrid/PHEV/EV’s a bad rep.
How many people do you supposed she has told about her “battery“ troubles and now are forever jaded against EV’s !

 

[Lytning]

For sure my 22 used to not enable the HVB in ACC mode. You could tell because CarScanner showed DC-DC disabled, and the A/C would blow warm air (A/C is powered by HVB). You could also watch the 12V SOC slowly go down.

But some update changed this, at least for me. Now when I turn on ACC mode, I get slightly cooler air and CarScanner shows the DC-DC enabled and the 12V battery as charging at 13.5+ volts. I suspect at some point all models of a certain build came with this behavior from the factory.

OTA's use to fail; because of poor 12V but that is rare now. So some update changed the behavior. If Ford wrote decent release notes, we would know which one.

I wonder if the 23B70 BMS Replacement had anything to do with this. I immediately noticed much higher 12 volt battery SOC's after the BMS replacement.

 

[bmwhitetx]

I wonder if the 23B70 BMS Replacement had anything to do with this. I immediately noticed much higher 12 volt battery SOC's after the BMS replacement.

Definitely a correlation for me. I had several OTA's fail for low 12V. The last was 6.8.0 in Dec '23. I got the BMS done in Jan '24. I have had 6 inhibit updates install 1st time since then including the really big BC 1.4.

 

[Lytning]

Definitely a correlation for me. I had several OTA's fail for low 12V. The last was 6.8.0 in Dec '23. I got the BMS done in Jan '24. I have had 6 inhibit updates install 1st time since then including the really big BC 1.4.

Congrats. I still don't have BC 1.4.

 

[TaxmanHog]

Congrats. I still don't have BC 1.4.

Right the with you, though I haven't been offered it as of yet ?

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