The hybrid is awesome! Just take the precautions when/if you are going to let it sit for a long time. I would buy this thing over and over again. 45 miles to the gallon over the last year and smooth ride with no shifting.
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Deep Sleep Maverick Hybrid Question
- Thread starter MaverickMom
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The main concern with that is safety. You don't want the high voltage system energizing at random times without the key in the vehicle.
Kia and Hyundai did have a 12v battery reset button on their hybrids which temporarily connects the HV battery to "jump start" the 12v battery via the HV battery.
I think that is literally what the Start button does in our Lariats. Press the button and see (in a dash plug) that it instantly shows 14.9-15.1 voltage. Like giving yourself a jump start all the time.
Not exactly. The push button start requires the 12v system to be running to work. That jump in voltage is the system starting up, the high voltage relay closing, and the dc-dc converter kicking on. The 12v resets on a Kia/Hyundai works even if the 12v battery is completely dead. So you hit it and then hit the push button start.
I'd think Kia's idea is better...
The system starts up well below 11.9...which is usually where my truck is at when sitting in deep sleep.
I AM annoyed by the whole deep sleep process, but in 355 days and only 3150 miles (so it sits a lot), it hasn't failed to start for me. I am glad I added remote start (2023), as that still works even when the truck is in deep sleep (a LOT of the time) and FordPass won't start it.
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If your battery is at 11.9 volts and you are getting deep sleep, there is something else wrong. The deep sleep should not activate until the voltage drops below 9.5 volts. Take it to the dealer and see if the BMS is properly reading battery voltage.
Yeah it honestly is a great feature, but mostly from necessity. Since they packaged the 12v battery in the same pack as the high voltage battery. So they had no way to jump start the vehicle using cables or a pack.
My guess is either patents or just consumers not understanding it is why other manufacturers haven't adopted it. Weirdly I think Kia didn't include it on their EVs. For my truck I personally have never experienced the deep sleep issue, and that includes parking my truck for a couple weeks while traveling. But I still carry a small jumper pack with me just in case.
I have a jump box that doubles as an air compressor. I put that in the truck very early out of caution, but only have had to use it for my neighbor's $100k Jeep Wagoneer...so far.
https://www.amazon.com/gp/product/B0BGHMYGHF/
Also on some of the Kia/Hyundais the system will actively "disconnect" the 12V battery as it approaches low charge and the 12V Reset reconnects that versus on Ford where the system just starts limiting features to alleviate potential key off draw.
I'v seen that "9.5 volt" document before. And I don't believe it.
I have 3 Fords that all go into Deep Sleep. The other is a 2020 Transit-based RV. It goes into Deep Sleep every 14 days (as it should), but I just changed the batteries last week (over 4 years old) as I got a deep sleep notice for it in less than the 14 day ritual. It was around 12.0 volts and I knew the batteries were aging out...they had a rough first year from the previous owner.
For the 2023 Maverick, had the most recent BMS update about 3 weeks ago along with the blink recall.
I think "load test the battery" is going to be my constant request when getting serviced. I haven't checked the 2024, but it goes into deep sleep similarly (it's only 6 weeks old). And both trucks live in garages that never get below 50 degrees.
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Yeah that is to avoid damaging the 12v battery, since they opted to use a lithium ion battery which doesn't handle being discharged below a certain level well. You don't want to destroy the 12v battery inside the high voltage battery pack just because someone left a light on.
Yeah, I had the deep sleep problem early last year that would not go away. It would go into deep sleep with 11.9 volts showing on my voltmeter. I pestered my dealer on a regular basis until now it does not go into deep sleep and I'm still showing 11.9 volts in the morning. I'm not sure what they did, but I'm happy with it.
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At 10.5 volts, your battery would be completely DEAD. There is no way at 9.5 volts the deep sleep mode is activated.
Read your manual
https://www.ford.com/support/how-to...y-does-my-ford-vehicle-enter-deep-sleep-mode/
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I've seen that...and it is complete BS. I've been managing 12V batteries for years, and there is no way it will still be ticking enough to let Ford know it was at 9.5V.
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