Normal LVB State of Charge Draw Down

[FLSpartan04]

I haven’t driven my truck as often the last few days as school just let out, and my normal routine of school and soccer drop offs has thankfully let up for a couple months. I noticed my battery level had dropped to 35% as I periodically check it in Ford.com and through the home assistant integration. I thought that was weird, as I believe it is supposed to recharge the LVB from the HVB when the SoC dips below 50%. Anyway, @TaxmanHog advised in another thread to run the vehicle to let the inverter recharge the 12v battery. That worked just fine and I was able to get it to 91%. I shut the truck off less than a couple hours ago, and it had already dipped to 85%. Should I be concerned? I didn’t think that the LVB drain would drop that fast. There are currently no loads, as I disconnected a MagSafe charger that I had recently installed in the cubby and the OBD scanner I usually leave plugged into the port. Because I normally started the truck and drove it at least twice a day, my LVB typically stayed in between 80 and 99%. Should I be concerned that it got as low as it did or that it is dropping SoC so fast? Appreciate the advice of this forum!

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[Maquis]

Have you had CSP 23B70 done yet? 12V BMS sensor replacement.

 

[FLSpartan04]

When I purchased the truck in March the CSP was there. However it disappeared within a couple weeks. I figured the dealer did it (as I asked them to make sure all open recalls were done before I picked it up as I drove 3.5 hours to get it. Anyway, it does not show the CSP on my account. My SoC has always been high, but then again I always drove at least two trips a day. Just wondering what the average “burn rate” I should expect on it. Looks like I dropped about 8% in 3 hours as of now. Is that normal?

 

[3121]

Make sure home assistant is not polling too often. That can trigger the truck to wake up more often.

When you asked the dealer to make sure they did all the recalls the probably just make a note “tell customer we did recalls”. Also the 12v is not a recall it’s a service bulletin which the customer technically is supposed to complain about before they replace it.

I would verify the 12v sensor is the updated part number.

 

[FLSpartan04]

I will have to check those threads to see the new part number. I agree with the dealer aspect, but I’d be surprised if they actually marked it closed unless they did it. As for home assistant that is a good point. It is set to poll every 15 minutes to not make the ford api mad . Also, it has been mostly down due to api changes. I just got it functional again today. I’ll have to keep an eye on it. I had it running for a month or two without issue (I actually keep a closer eye on the SoC when it’s working, because it’s on my dashboard).

 

[Maxx]

I think BMS with -AC or -AD after MK3T-10C652- are bad and any others like -BA are OK.

Keep in mind there are a lot of things like the light in the center console stay on for a while after you turn off the truck and different modules turn off at different times.

And you can take the scanner off to see if something changes. Comparing in span of at least 24 hours (longer if you can) may be more conclusive.

 

[FLSpartan04]

Yes. I’ve got everything unplugged now. I am going to do some A/B testing with and without loads plugged into the 12V circuit and see what the draw is. Funny enough when I checked my truck just now it was at 89% SoC. Ford was reporting 83 until I powered on the truck then it must have got an update and matched the actual state of charge (at least the one reported through CarScanner). So the FordPass reporting may not always be so accurate. I’ll keep an eye on it. Thanks all for the assist.

 

[RickLightning]

Every time you wake the vehicle you drain the 12v...

 

[Adventureboy]

There are lots of threads on this one. The truck shuts many modules off in a sequence, eventually shutting down the modem and going into deep sleep mode when the SOC drops too far. When I tested, this seemed to be around the high 40s% on my truck using an independent battery monitor, but I'm sure it varies depending on the state of the BMS sensor CSP and the battery's health. It charges the LVB from the HVB however the actual SOC won't be reflected online until the truck exits deep sleep mode. Powering ON kicks everything back on (including the modem) and the accurate LVB SOC will be presented again online. The easiest way to check if it is in deep sleep is to press the lock button on Ford Pass while outside Bluetooth range. If the truck is connected, it will show the green check on the lock momentarily. If in deep sleep mode, Locking will not work. Note: as @RickLightning says, if you do this often, it drains the LVB faster since it lights up many modules that are normally shut down a while after you power off.

As @3121 mentioned, your Home Assistant may throw a monkey wrench into the way this works since it is polling the truck and may keep many things alive that would normally be shut down to conserve LVB, draining it faster and preventing the truck from its normal processes. Maybe do a test with the HA link disabled and see what it does.

I'm playing with HA too, but not deep in yet.

 

[bmwhitetx]

As for home assistant that is a good point. It is set to poll every 15 minutes to not make the ford api mad . Also, it has been mostly down due to api changes. I just got it functional again today.

I don't have HA poll that often; I don't drive much and HA impacted LVB at 15 minute polling. I had mine set at 2 hours but recently changed to 8 hours (28800 seconds).

As for the automatic recharge below 50% concern, I got the faulty PCM update and was told to monitor 12V and to plug into a charger every few days. . Sure enough I'm now sitting at 37% LVB after driving only 5 miles the last 10 days.

When it was sitting on the dealer lot waiting for repair the LVB drained below 40%-50% a couple of times and each time the truck charged it back up.

 

[FLSpartan04]

I don't have HA poll that often; I don't drive much and HA impacted LVB at 15 minute polling. I had mine set at 2 hours but recently changed to 8 hours (28800 seconds).

As for the automatic recharge below 50% concern, I got the faulty PCM update and was told to monitor 12V and to plug into a charger every few days. . Sure enough I'm now sitting at 37% LVB after driving only 5 miles the last 10 days.

When it was sitting on the dealer lot waiting for repair the LVB drained below 40%-50% a couple of times and each time the truck charged it back up.

Not a bad idea. Maybe I’ll split the difference and set mine to 4 hours. I drove enough that mine was rarely less than 80, so I was pretty surprised to see it drop all the way down to 35. I guess I had confidence that the truck would charge it back up. I definitely don’t have the faulty update (or at least that specific one) my last update was whatever the redistribution of 6.2 was called. Anyway, I will back off the HA polling and keep a general eye on it, to make sure it doesn’t drop too low.

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