Deep Sleep Mode – More common?

[Mx5]

Hi:

I think the deep sleep mode issue might be more common than it appears. I’ll explain. In March, 2025, I bought a new 2025 Maverick XL Hybrid. Drove it often until my summer car came out of storage. Then, no so much.

On August 11, 2025, I returned from a 4 days vacation and when I tried to start the Maverick, it was dead. I jumped it and it ran 5 minutes before shutting down. I jumped it again and then drove around for 20 to 25 minutes. Next day I brought it to the dealer and battery was replaced with an AGM. (I was told the original battery was also an AGM.). Truck was fine until it sat again for a period of time.

In early September, I did not drive it for 7 days and once again it would not start. This time, it was towed to the dealer. After 7 days, I picked it up. Problem: SSM 53891- 12v battery drain due to software installed in air conditioning control module. Battery was also replaced, again. Drove it home and let it sit for 7 days and, as I predicted, truck went into deep sleep mode and would not start. I’m on my way to the dealer and will have them tow it again.

I began to think that maybe there are many more trucks affected by whatever the issue is. My hypothesis is that most owners driver their trucks frequently. Perhaps everyday or 3 or 4 times per week. I wonder if more owners let their truck sit for a week, if it would enter the deep sleep mode and not start. Perhaps some Maverick hybrid owners will be willing to try this and see if the deep sleep mode problem is more widespread. If anyone does, please post your result here.

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[ZABSMAV]

Hi:

I think the deep sleep mode issue might be more common than it appears. I’ll explain. In March, 2025, I bought a new 2025 Maverick XL Hybrid. Drove it often until my summer car came out of storage. Then, no so much.

On August 11, 2025, I returned from a 4 days vacation and when I tried to start the Maverick, it was dead. I jumped it and it ran 5 minutes before shutting down. I jumped it again and then drove around for 20 to 25 minutes. Next day I brought it to the dealer and battery was replaced with an AGM. (I was told the original battery was also an AGM.). Truck was fine until it sat again for a period of time.

In early September, I did not drive it for 7 days and once again it would not start. This time, it was towed to the dealer. After 7 days, I picked it up. Problem: SSM 53891- 12v battery drain due to software installed in air conditioning control module. Battery was also replaced, again. Drove it home and let it sit for 7 days and, as I predicted, truck went into deep sleep mode and would not start. I’m on my way to the dealer and will have them tow it again.

I began to think that maybe there are many more trucks affected by whatever the issue is. My hypothesis is that most owners driver their trucks frequently. Perhaps everyday or 3 or 4 times per week. I wonder if more owners let their truck sit for a week, if it would enter the deep sleep mode and not start. Perhaps some Maverick hybrid owners will be willing to try this and see if the deep sleep mode problem is more widespread. If anyone does, please post your result here.

You are correct in your hypothesis. The deep sleep problem is quite widespread.

We should all be able to not drive for a week (or more) and expect it to start right up and not be in the battery fail mode. The change to AGM, as you proved, did not fix it. Nor did the supposed "fix" by the AC Control Module software update.

We are all still awaiting Ford's promised fix.

 

[lm126027]

Don't have a hybrid, but recently have had (twice) the message that they were shutting down things as the battery was low.. Weird... Could the battery be going? Left truck in Jackman ME for a week last winter while I went snowmobiling in Canada and it got buried (2 large snow storms) and it started via the remote then.

 

[710-oil-614]

Yes this has been widespread. It is very common.

 

[grandpa_disney]

I drive my 24 XLT hybrid about once a week. Sometimes in Fordpass I see that it is in deep sleep mode. Has never failed to start, but has me a bit concerned that it might fail in the future.

This is not a new problem for Ford. A CoWorker had a 2015 or so Mustang GT that got driven very rarely. Mostly kept in the garage and taken out during the summer. It was dead all the time. He finally sold it.

 

[Gullzway]

That's not deep sleep, that's a bad battery or something else.

Deep sleep just disables intelligent access on the passenger side and the dome lights, as well as remote start with the app.

 

[grandpa_disney]

That's not deep sleep, that's a bad battery or something else.

Deep sleep just disables intelligent access on the passenger side and the dome lights, as well as remote start with the app.

Deep Sleep is to preserve battery, once it has been depleted past a certain threshold. What is happening is that a parasitic drain is happening that will deplete the 12V battery past the point where it will start the vehicle. What ever Deep Sleep cuts off is not the cause of the drain. Ford engineering thought it was an issue in the AC control module, but it is hit or miss. I suspect they got it wrong. On the mustang they never had an answer.
Parasitic drains can be very hard to track down given all the variables.

 

[HeyBales]

Hi:

I think the deep sleep mode issue might be more common than it appears. I’ll explain. In March, 2025, I bought a new 2025 Maverick XL Hybrid. Drove it often until my summer car came out of storage. Then, no so much.

On August 11, 2025, I returned from a 4 days vacation and when I tried to start the Maverick, it was dead. I jumped it and it ran 5 minutes before shutting down. I jumped it again and then drove around for 20 to 25 minutes. Next day I brought it to the dealer and battery was replaced with an AGM. (I was told the original battery was also an AGM.). Truck was fine until it sat again for a period of time.

In early September, I did not drive it for 7 days and once again it would not start. This time, it was towed to the dealer. After 7 days, I picked it up. Problem: SSM 53891- 12v battery drain due to software installed in air conditioning control module. Battery was also replaced, again. Drove it home and let it sit for 7 days and, as I predicted, truck went into deep sleep mode and would not start. I’m on my way to the dealer and will have them tow it again.

I began to think that maybe there are many more trucks affected by whatever the issue is. My hypothesis is that most owners driver their trucks frequently. Perhaps everyday or 3 or 4 times per week. I wonder if more owners let their truck sit for a week, if it would enter the deep sleep mode and not start. Perhaps some Maverick hybrid owners will be willing to try this and see if the deep sleep mode problem is more widespread. If anyone does, please post your result here.

Ditto to that not being a deep sleep issue - which isn't an "issue" it's an effect from several things.
Deep Sleep Mode is one of the battery saver functions - disables the modem from an hourly ping to keep the network connection active for remote access. So now 25 mA draw instead of 50-80 mA spikes hourly.
14 days non-start - to stop the micro-drain since you may be non-starting for who knows how long.
Low Voltage or SOC% - so there's battery left to start the truck.

In the vast majority of cases when you read all the threads - deep sleep mode is doing exactly what it's supposed to - conserve battery so you can start.

The number reporting actually dead batteries with no start is very rare actually - and is usually a different reason found.
Shoot - many start their trucks and take them in and battery is found bad and replaced under warranty.

While that SSM took care of 1 parasitic draw Ford must have thought was the worst offender (and was never reported in threads here before that I saw), the more common TCU module has been reported as an issue several times, obviously other modules can go nuts too with bad sensor or module and remain at high power draw way longer than 75 min expected.

They do indeed need to do the longer troubleshooting on yours.
That SSM was to stop doing that since it's a big chunk of time.

 

[HeyBales]

Deep Sleep is to preserve battery, once it has been depleted past a certain threshold. What is happening is that a parasitic drain is happening that will deplete the 12V battery past the point where it will start the vehicle. What ever Deep Sleep cuts off is not the cause of the drain. Ford engineering thought it was an issue in the AC control module, but it is hit or miss. I suspect they got it wrong. On the mustang they never had an answer.
Parasitic drains can be very hard to track down given all the variables.

Deep Sleep disables the modem - that's it.

Indeed that SSM was for what they thought was an infrequent parasitic drain - not seen often.

What is happening in the vast majority of deep sleep mode cases is not an excessive drain - it's undercharging.
So much so sulphation ruins the battery and then it's a losing game of how high to charge without overcharging rest of it.

Yes - this thread is a parasitic drain - most aren't on deep sleep mode.

 

[grandpa_disney]

Deep Sleep disables the modem - that's it.

Indeed that SSM was for what they thought was an infrequent parasitic drain - not seen often.

What is happening in the vast majority of deep sleep mode cases is not an excessive drain - it's undercharging.
So much so sulphation ruins the battery and then it's a losing game of how high to charge without overcharging rest of it.

Yes - this thread is a parasitic drain - most aren't on deep sleep mode.

Agree with the modem, but seems to disable the dome light as well. So I wonder what else it disables that they do not tell us about. Perhaps they should put more on the disable list!

 

[AutobahnSHO]

We got quite a few deep sleep notices the first year, not as many later- maybe once a month since then. Bought new April 2023, 21k miles now, original battery still, knock on wood has always started right up.

 

[JetFixxxer]

I started to get the messages last month. I get them at least three to four times a week and my commute is about 1/2 hr one way.

I get the notifications, but doesn't save them all into my Ford App messages. I received one this morning after driving almost a hour.

 

[HeyBales]

Agree with the modem, but seems to disable the dome light as well. So I wonder what else it disables that they do not tell us about. Perhaps they should put more on the disable list!

Deep Sleep Mode does not, normal Battery Saver does.
Rest of the items require doors opening closing, ect - really doesn't matter when it sits for a long time, those won't help save battery. Keyless entry disables passenger touch access, perhaps it eventually gets to driver side. Then remote would be required, perhaps eventually the key!

From manual they do tell you:
Why do my headlamps turn off when I have them switched on when I switch my vehicle off?

• The battery saver turns the headlamps off after a short period of time after you switch your vehicle off.

Why do my courtesy lamps or interior lamps turn off when I have them switched on when I switch my vehicle off?

• The battery saver turns the courtesy lamps and interior lamps off after a short period of time after you switch your vehicle off.

Battery Management System (If Equipped)
The system monitors battery conditions and takes action to extend battery life. If the system detects excessive battery drain, it temporarily disables some electrical systems to protect the battery.
Systems included are:

• Heated rear window.
• Heated seats.
• Climate control.
• Heated steering wheel.
• Audio unit.
• Navigation system.

A message may appear in the instrument cluster to alert you that battery protection actions are active. This message is only for notification that an action is taking place, and not intended to indicate an electrical problem or that the battery requires replacement.

Note: Your vehicle has a battery saver feature that shuts your vehicle off when it detects a certain amount of battery drain, or after approximately 30 minutes of inactivity in accessory mode.

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