System Off To Save Battery

[airline tech]

19 Ranger XLT, I am currently on my 4th battery since new! First two were covered under warranty, I have replaced the third and now 4th. Third one was done at Ford dealership where I go, 4th I did because of being a weekend and needing the truck. We had been on a 3 week road trip in a rented RV, going into week 2 to 3 on the road I decided to check my Ford app to see what was going on, mainly curiosity but also I was concerned because of battery failures in the past. App said truck had gone to sleep to preserve battery. At that point I knew I should have disconnected the negative cable before leaving...lesson learned. When we returned I was going to pull the truck out so we could unload the RV, truck was so freaking dead it had nothing, was able to grab my volt meter and it showed 3 volts across the terminals! I think this qualifies as dead. Battery was purchased in January 2025, basically new. Meanwhile my wife goes to her Tacoma parked next to mine and it starts right up...yup I was butt hurt. Threw on the charger for an overnighter. Next morning, nope dead, battery would not recover. Battery replaced under warranty, attempted to acquire a parasitic draw, but not sure if I had the hood completely closed. I had locked the car so it would go to sleep, came back an hour later for a reading, it was showing a draw of .14 ma. Should be .05ma if Im right.
Truck has 77K, have had no other issues except the battery. On extended warranty so I'm going to have to take it in. What I hate about that is if Ford finds no issues I have to pay 200 for diag. If they do find an issue and it's covered I'll pay 100....ugh either way...

To get a true reading - you have to manually push the hood latch down (2-Detents)
1st detent = popped open and under hood release holding the hood
2nd detent = fully closed - This closes the Hood Ajar Switch

To Reset it- Pull The Hood Release Handle in the cab and it will release back open.

I will say though that something is off, be it parasitic draw or with the charging system including the BMS sensor itself.
Even at 3-weeks it should not be anywhere near 3-volts on the battery, so either a high draw or the battery is not being charged properly.
Definitely needs a deep T-Shoot for this:
Questions
1. How often do you hear the Wastegate Actuator cycle when the truck is parked?
2. When you open the drivers door after it has been parked, do you hear it cycle?

I am looking for (Wake Circuit) powering down? completely or is the TCU excessively waking the circuit by constantly checking in on (health)
Even with that - Deep Sleep Message and Action - Comes in play @ about 11.5 Volts, so if operating properly all but bare minimum modules should completely shut down and the TCU becomes disabled.
So something else is pulling power I think - outside of the modules control- possible extra aftermarket add on's Lighting, Winch ,Camera etc.

Have you ever monitored charging voltage while driving - plug in voltmeter (in the PowerPoint)?
This would show if the charging system is operating within normal for the Ranger.

So it needs to be T-Shot down to - System undercharging the battery and its consistently killing the battery cells or an actual unwanted draw

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[TJC]

I suspect a bad cells. This isn't just sulfation at work here. Ford is putting entirely too much stress on these batteries. I suspect that sulfur and lead particulates are settling to the bottom of the battery and shorting the cells.

I'm seeing the same symptoms in my 2023 CX-5. Low internal resistance, but battery loses charge very easily. It is still behaving normally, but the trend is not good. I think that I may have exacerbated the issue by disconnecting the antenna instead of pulling the plug on the TCU. It may be constantly trying to connect to "Momma" to send a data report after each trip. It doesn't connect so it keeps trying.

I noticed the bad cell warning lamp lightly glowing on my expensive BatterMinder 8 amp charger when I charged it last week. It goes out completely when the charge cycle completes, but I don't like where this is going. I have yet to disable the modem on the CX-5, and I wish I had disabled the TCU on my 2020 Ranger sooner.

Time to check dark current drain.

 

[airline tech]

I suspect a bad cells. This isn't just sulfation at work here. Ford is putting entirely too much stress on these batteries. I suspect that sulfur and lead particulates are settling to the bottom of the battery and shorting the cells.

I'm seeing the same symptoms in my 2023 CX-5. Low internal resistance, but battery loses charge very easily. It is still behaving normally, but the trend is not good. I think that I may have exacerbated the issue by disconnecting the antenna instead of pulling the plug on the TCU. It may be constantly trying to connect to "Momma" to send a data report after each trip. It doesn't connect so it keeps trying.

I noticed the bad cell warning lamp lightly glowing on my expensive BatterMinder 8 amp charger when I charged it last week. It goes out completely when the charge cycle completes, but I don't like where this is going. I have yet to disable the modem on the CX-5, and I wish I had disabled the TCU on my 2020 Ranger sooner.

Time to check dark current drain.

I think this is deeper than a bad battery, something is wrong with a 2019 being on battery #4 and 77K - something else is triggering it.

 

[SFB]

To get a true reading - you have to manually push the hood latch down (2-Detents)
1st detent = popped open and under hood release holding the hood
2nd detent = fully closed - This closes the Hood Ajar Switch

To Reset it- Pull The Hood Release Handle in the cab and it will release back open.

I will say though that something is off, be it parasitic draw or with the charging system including the BMS sensor itself.
Even at 3-weeks it should not be anywhere near 3-volts on the battery, so either a high draw or the battery is not being charged properly.
Definitely needs a deep T-Shoot for this:
Questions
1. How often do you hear the Wastegate Actuator cycle when the truck is parked?
2. When you open the drivers door after it has been parked, do you hear it cycle?

I am looking for (Wake Circuit) powering down? completely or is the TCU excessively waking the circuit by constantly checking in on (health)
Even with that - Deep Sleep Message and Action - Comes in play @ about 11.5 Volts, so if operating properly all but bare minimum modules should completely shut down and the TCU becomes disabled.
So something else is pulling power I think - outside of the modules control- possible extra aftermarket add on's Lighting, Winch ,Camera etc.

Have you ever monitored charging voltage while driving - plug in voltmeter (in the PowerPoint)?
This would show if the charging system is operating within normal for the Ranger.

So it needs to be T-Shot down to - System undercharging the battery and its consistently killing the battery cells or an actual unwanted draw

Thank you for your advice
It is charging, I have an OBD Fusion that I can read on my phone while driving. I will redo the parasitic draw test again and this time latch the hood completely. The current battery is new as of mid July. I believe it to be a parasitic draw as the charging system has been checked on my last oil change. Was also told when exchanging my battery at Ford that they had a bad run of batteries, they are made by Interstate Battery.
Thanks again..

 

[TJC]

Was also told when exchanging my battery at Ford that they had a bad run of batteries, they are made by Interstate Battery.
Thanks again..

It is very difficult to determine the age of a "new" battery. Those date stickers are applied at the time of sale. The battery could have been sitting for a year or more... on a charger bank. They sell them as new as long as the internal resistance is below a given threshold. They would not tell me what the threshold limit was.

I challenged a auto store employee when he brought me out a 4 month old battery (according to the sticker) and when I told him I would not accept a battery that old he took it in the back and simply replaced the sticker! I noticed that it was the same battery that he had taken back, but it had a newer sticker applied... he confessed that they apply the sticker at the time of sale. But that they closely followed the manufacturers policy.

There no longer is a manufacture date per se on new batteries. At least not on the last 2 that I have purchased.

 

[airline tech]

19 Ranger XLT, I am currently on my 4th battery since new! First two were covered under warranty, I have replaced the third and now 4th. Third one was done at Ford dealership where I go, 4th I did because of being a weekend and needing the truck. We had been on a 3 week road trip in a rented RV, going into week 2 to 3 on the road I decided to check my Ford app to see what was going on, mainly curiosity but also I was concerned because of battery failures in the past. App said truck had gone to sleep to preserve battery. At that point I knew I should have disconnected the negative cable before leaving...lesson learned. When we returned I was going to pull the truck out so we could unload the RV, truck was so freaking dead it had nothing, was able to grab my volt meter and it showed 3 volts across the terminals! I think this qualifies as dead. Battery was purchased in January 2025, basically new. Meanwhile my wife goes to her Tacoma parked next to mine and it starts right up...yup I was butt hurt. Threw on the charger for an overnighter. Next morning, nope dead, battery would not recover. Battery replaced under warranty, attempted to acquire a parasitic draw, but not sure if I had the hood completely closed. I had locked the car so it would go to sleep, came back an hour later for a reading, it was showing a draw of .14 ma. Should be .05ma if Im right.
Truck has 77K, have had no other issues except the battery. On extended warranty so I'm going to have to take it in. What I hate about that is if Ford finds no issues I have to pay 200 for diag. If they do find an issue and it's covered I'll pay 100....ugh either way...

Curiosity got me wandering - so I did a quick overnight monitor of the system to find what is actually normal draw for the truck.
Granted - I forgot (1-Thing) as I did not note any TCU (check-Ins) while out at the truck.
I wish I would have (forced a refresh) to see exactly how much amperage is being drawn during those events.

Most specs that I can find are anything under 50 mA is normal to see with the engine off with 25 to 30 mA is the average - however I noted that it stayed under 0.014 mA after 2.0 hrs

I did have some fluctuation of readings prior to me actually recording them, but I wanted to ensure accurate readings after all modules should be asleep
Sometime between 5.0 & 8.0 hours - The Readings went steady @ 0.009 mA

The 75-Minute mark is important, due to the fact that it is a known Time-Out point for the console power points, that's why I made sure to check it at exactly 75-Minutes and saw the drop (live)
Granted - They were empty

Here is my reference results

 

[SFB]

Curiosity got me wandering - so I did a quick overnight monitor of the system to find what is actually normal draw for the truck.
Granted - I forgot (1-Thing) as I did not note any TCU (check-Ins) while out at the truck.
I wish I would have (forced a refresh) to see exactly how much amperage is being drawn during those events.

Most specs that I can find are anything under 50 mA is normal to see with the engine off with 25 to 30 mA is the average - however I noted that it stayed under 0.014 mA after 2.0 hrs

I did have some fluctuation of readings prior to me actually recording them, but I wanted to ensure accurate readings after all modules should be asleep
Sometime between 5.0 & 8.0 hours - The Readings went steady @ 0.009 mA

The 75-Minute mark is important, due to the fact that it is a known Time-Out point for the console power points, that's why I made sure to check it at exactly 75-Minutes and saw the drop (live)
Granted - They were empty

Here is my reference results

Interesting,
I was getting .14 ma after an hour, the doors were locked but I didn't have the hood completely latched. I need to try again but do an overnight reading. I use a Fluke MM, which I borrow from work.
Appreciate your input, thanks

 

[RangerBill]

Interesting,
I was getting .14 ma after an hour, the doors were locked but I didn't have the hood completely latched. I need to try again but do an overnight reading. I use a Fluke MM, which I borrow from work.
Appreciate your input, thanks

Did you mean .14 amps? That would be 140 mA (milliamps).
.14 milliamps is an extremely small value of current and is an unlikely reading for your truck.

Amps x 1000 = milliamps (mA)
Milliamps divided by 1000 = Amps

Some of the values being used in today's posts are off by a factor of 1000.

 

[airline tech]

I updated the Test Results to include the (Ford Pass) TCU Check-In Results

 

[SFB]

I suspect a bad cells. This isn't just sulfation at work here. Ford is putting entirely too much stress on these batteries. I suspect that sulfur and lead particulates are settling to the bottom of the battery and shorting the cells.

I'm seeing the same symptoms in my 2023 CX-5. Low internal resistance, but battery loses charge very easily. It is still behaving normally, but the trend is not good. I think that I may have exacerbated the issue by disconnecting the antenna instead of pulling the plug on the TCU. It may be constantly trying to connect to "Momma" to send a data report after each trip. It doesn't connect so it keeps trying.

I noticed the bad cell warning lamp lightly glowing on my expensive BatterMinder 8 amp charger when I charged it last week. It goes out completely when the charge cycle completes, but I don't like where this is going. I have yet to disable the modem on the CX-5, and I wish I had disabled the TCU on my 2020 Ranger sooner.

Time to check dark current drain.

I've had 3 batteries go teats up on me, Parts guy at the Ford dealer said they have had issues. First two were checked at Ford, also my charging system and batteries were bad, the third one I purchased was the one that died while I was on vacation. Gone for 3 weeks, when I got home a completely dead truck, that was where I measured 3 volts across the posts, battery would not take a charge, tried overnight, next day was the same 3V. So Im not sure if I got another bad battery or if there is something else going on. My battery history points to another bad one though

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