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Voltage/battery management issue

Cdubya

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#21
You don't have one of those portable jump starters/power bricks? I'd be curious if it would crank briskly with more power connected. I would still think there's an issue with the battery even though voltages are good and it tests out good. Certainly could be bad starter or starter circuit but plenty have had new batteries be duds.
 

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Thread Starter #22
You don't have one of those portable jump starters/power bricks? I'd be curious if it would crank briskly with more power connected. I would still think there's an issue with the battery even though voltages are good and it tests out good. Certainly could be bad starter or starter circuit but plenty have had new batteries be duds.
I do have one of those and no it will not start with it. I have had no issues with my jump box on other vehicles in the past including the explorer but it will not start with it now. The only way I have gotten it started is with a jump start. But, not every try works. Sometimes I have to connect it and leave the running vehicle running for 5+minutes before it works.
 

powerboatr

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#23
I have noco portable jump thing
It flat outs out the amps and I have used it twice on other people's vehicles
Then it takes hours to recharge
I have one in both vehicles
 

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#24
I do have one of those and no it will not start with it. I have had no issues with my jump box on other vehicles in the past including the explorer but it will not start with it now. The only way I have gotten it started is with a jump start. But, not every try works. Sometimes I have to connect it and leave the running vehicle running for 5+minutes before it works.
Only time I had trouble with a jump start or a lithium pack starting was due to a bad battery. Like dead cell bad. I know it’s new and you had it tested but the symptoms sure look like a battery issue. Be nice if you could somehow swap with a known good battery. Know any local ST owners?

Too bad I was in SW Florida 10 days ago.


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Thread Starter #25
Only time I had trouble with a jump start or a lithium pack starting was due to a bad battery. Like dead cell bad. I know it’s new and you had it tested but the symptoms sure look like a battery issue. Be nice if you could somehow swap with a known good battery. Know any local ST owners?

Too bad I was in SW Florida 10 days ago.


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I agree, almost everything about this points to a bad battery. And I really thought that would be the case but after testing it myself using my tester and the place I bought it from testing it good was well... I'm stuck. Even if that battery is bad, their tester said it's good so getting it swapped/warranted would be hard.

I don't know other st's around here but I have 2 other cars. Those batteries wouldn't have the same specs as the explorer but for a quick test, they could work. My v8 mustang has an optima in it with a higher cca rating.
 

Cdubya

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#26
I would try disconnecting that battery and using the jumper cables to connect the Mustang battery to the explorer leads, ie. take the Explorer battery completely out of the picture
 

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#27
My guess would be the starter. You mentioned that the battery was showing good voltage at draw according to your tests and the battery distributor's testing.
These starters are prone to overwork failure especially because of the start/stop feature which I think is a ploy for stealership repair.

After a while, these starter motors will generate metallic dust through excessive use which can cause a myriad of starting problems, including a total short out. The dust spreads onto the armature and starts to compromise the winds. I also have a 2020 and had to replace mine a few months ago because the starter flat shorted out. In my case, it kept blowing the starter fuse but in yours, if it is partially shorted, it can cause a big amp draw which seems to be the problem in your case. Even with the help of your starting block, it was unsuccessful.

With that said, that would be my next point of focus. Either way, good luck!
 

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#28
I would try disconnecting that battery and using the jumper cables to connect the Mustang battery to the explorer leads, ie. take the Explorer battery completely out of the picture
Being as I suspect the starter in the Explorer, I would try the reverse and jumper the Explorer battery to the Mustang in an attempt to start the V8. I think that would better rule out the battery with a successful start if I am correct. I would be assuming that the Mustang has a sound starting system. If I am not correct, it would be an easier task to replace the battery for sure.
 

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Thread Starter #29
Maybe an inconclusive test... But here is what I did:

1. Verified explorer still not starting
2. Verified mustang starts
3. Checked voltage on mustang. 12v off, 13.8 volts running.
4. Completely disconnected explorer battery from the explorer and connected it to mustang.
5. Verified mustang had power. 12v off
6. Try to start mustang and nothing, completely shuts off. Since it killed power, I lost my log of voltage at the obdii port but it was 12v after it came back up.
7. Connected mustang battery to explorer. Verified power, 12v off.
8. Try to start explorer and lose power.


Soooooooo... It does seem like the explorer battery has issues. It also still seems like it could be something else. Looking at the mustang battery specs, its not as high as I thought it was. It's only 720cca vs 760 for the explorer. That might explain why it wouldn't start the explorer but if the explorer battery were good, I would expect it to start the mustang and it didn't.
 

Cdubya

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#30
So you did the switcheroo for both cars and neither could start the other car?? well not sure that tells you anything. I don't think the CCA difference should hold back the mustang battery from starting the Explorer.

For me, I would avoid the dealer at all cost. They'll probably charge you a $250 diagnostic fee. I'd rather assume the battery is faulty and buy another. if that didn't work then replace the starter.

I usually get my batteries at Sam's Club. They would probably pro rate it no questions asked if i said it was faulty.
 

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Thread Starter #31
So you did the switcheroo for both cars and neither could start the other car?? well not sure that tells you anything. I don't think the CCA difference should hold back the mustang battery from starting the Explorer.
Correct. Mustang battery starts mustang but not explorer. Explorer battery doesn't start anything.
 

powerboatr

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#32
Correct. Mustang battery starts mustang but not explorer. Explorer battery doesn't start anything.
720 or 760 is not the issue unless its freaking cold as witches you know what
the 3.0 spins over pretty easy compared to the mustang v8..it is a v8 right :love:
so the explorer battery has been ruined by the starter or something that drew huge amps and volts....like a partial short or the like
i would get a new battery at least when they replace the starter...
does car smell like ozone under the hood when you try to start it?
damm the bad luck
 

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#33
Correct. Mustang battery starts mustang but not explorer. Explorer battery doesn't start anything.
One quick question:
When you swapped the batteries, did you do it via jumper cables or did you actually put the vehicle clamps on the batteries?
Depending on your jumper cable connections, I've never concluded that jumpers transfer the full current as opposed to a direct connect to the vehicle cables. I would find that test inconclusive if you used the jumper cable route.
If on the other hand, you made actual direct installation connections, then you def have a more conclusive outcome. In that regard, my opinion, based on your results, would be that the Explorer has a faulty starter circuit and your new battery has been compromised because of it. That doesn't rule out that your new battery could have been faulty also from the git go.
 

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Thread Starter #34
One quick question:
When you swapped the batteries, did you do it via jumper cables or did you actually put the vehicle clamps on the batteries?
Depending on your jumper cable connections, I've never concluded that jumpers transfer the full current as opposed to a direct connect to the vehicle cables. I would find that test inconclusive if you used the jumper cable route.
If on the other hand, you made actual direct installation connections, then you def have a more conclusive outcome. In that regard, my opinion, based on your results, would be that the Explorer has a faulty starter circuit and your new battery has been compromised because of it. That doesn't rule out that your new battery could have been faulty also from the git go.
I did it via the jumper cables. The mustang battery is wider than the explorers and will not easily fit in the tray. Could probably make it work somehow but didn't really feel like doing that.

At this point I think it is a combination of both the battery and something in the starting circuit. I just got off the phone with my dealer and am able to bring it on Friday instead of Tuesday. I'll have to figure something out with the battery as they said they may have to replace it in order to get it started and do the diag. If they can give me a print out saying the battery was bad hopefully I can use that with the company I bought it from.
 

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#35
I have nothing connected to the vehicle (no lights, dashcam, no aftermarket stereo.)

I replaced the battery myself and did reset the bms when I did it.

After leaving it overnight, not on the charger, I don't see voltage below 12.

Last night it was connected to my charger. This morning, 12.4v at the battery, 12.2v read using my scanner at the obdii port. Tried to start, voltage on the scanner went down to 7.5v while cranking then back up to 12.2 after measured at the battery again at 12.4. Really hoping it's just the battery.
I'm curious to see what you figure out. I had this issue with my '17 Fusion and was the most frustrating thing to explain to the dealer what the problem was because they could never duplicate it. So I would record me starting the car at different times of the day to show how inconstant it was. Turned out they did not reset the BMS when they replaced the battery. After that I never had an issue and was hoping that would be good suggestion for you.

Good luck and keep us posted.
 

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#36
I did it via the jumper cables. The mustang battery is wider than the explorers and will not easily fit in the tray. Could probably make it work somehow but didn't really feel like doing that.

At this point I think it is a combination of both the battery and something in the starting circuit. I just got off the phone with my dealer and am able to bring it on Friday instead of Tuesday. I'll have to figure something out with the battery as they said they may have to replace it in order to get it started and do the diag. If they can give me a print out saying the battery was bad hopefully I can use that with the company I bought it from.
Daggone, if your battery is still measuring 12.4v at static condition and the stealership has more than adequate starting equipment, I don't see how they need to replace the battery just to get it started! They, as usual, want in your pocket before they even start.
If it is indeed the starter or something else in the starter circuit, a new battery is not the answer at that point. They're wasting your diag money!

Will it still start with the new battery and a jump augment from another vehicle?
 

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Thread Starter #37
Daggone, if your battery is still measuring 12.4v at static condition and the stealership has more than adequate starting equipment, I don't see how they need to replace the battery just to get it started! They, as usual, want in your pocket before they even start.
If it is indeed the starter or something else in the starter circuit, a new battery is not the answer at that point. They're wasting your diag money!

Will it still start with the new battery and a jump augment from another vehicle?
The first time I had to jump it, it started right up like that. Later that same day, it wouldn't start again and a jump with the same vehicle didn't work initially. I had to have it connected and running for 5+ minutes before it would start. I haven't tried a jump since then. I will have to try it again tomorrow night or have it towed for my appointment Friday morning (dropping it off Thursday night.)

We have a Ford extended warranty so whatever this is, minus the battery, should be covered.
 

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#38
The first time I had to jump it, it started right up like that. Later that same day, it wouldn't start again and a jump with the same vehicle didn't work initially. I had to have it connected and running for 5+ minutes before it would start. I haven't tried a jump since then. I will have to try it again tomorrow night or have it towed for my appointment Friday morning (dropping it off Thursday night.)

We have a Ford extended warranty so whatever this is, minus the battery, should be covered.
Personally, I would connect your jumper vehicle and let it charge for 5 minutes and start it if it will on Thurs night. Then drop it off and call service in the morning and tell them it starts with a proper battery boost and delay replacing the battery until they diag the problem.
No sense in charging you with a new battery until then.
Good luck!
 



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