2020 Wont Start, lights flicker, no clicking, replaced battery, now what?

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fordguy987

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I have a 2020 expedition that has started randomly not starting since i bought it 2 months ago. 40k miles 4x4 model. Car will randomly not start after sitting overnight or in parking lot for hours at a time. Lights flicker in dash but brake pedal goes stiff and car electronics just flash. Bought new batter a month ago since voltages and CCAs were low according to local auto parts store. Now it’s doing it again. I have the battery on a battery maintainer which seems to fix the issue after an hour or so. Also, when this issue happens the remote start function sometimes works as a work around. I have an appointment with the ford service but they couldn’t get me in until the 7th of August. Any ideas?
Is this a part of any known issues? Something seems to be drawing power from batt when car is off I think. And the auto parts store had a hard time checking the battery and alternator since there was something drawing battery power… took it to ford and they hooked it up to their battery tester and said the voltage and amps were reading low so that’s why I replaced it.
Edit- forgot to mention that advance auto where I bought the replacement agm battery checked computer for codes but there were none in the computer.
 

BlackBetty

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Edit- forgot to mention that advance auto where I bought the replacement agm battery checked computer for codes but there were none in the computer.
The PCM is dropping codes if the battery is losing charge… that’s my guess.

Have you noticed if anything is staying on longer than usual. I.E., had a coworker with similar issues on an F-150. I found that the door switch on his rear passenger door was inop. Causing the truck to think door was still open. Did a bit more troubleshooting to find it was a faulty switch; I got the lights to go out by shorting the switch. Put it back together so he could take it in for warranty repair. He was one of those “only the dealer repairs my truck” guys. Whatever!!!

He was very reluctant to even let me look at it… much less allow me to take the door apart. Besides the fact I’ve got more years working on cars than he’s been alive, I’m also a helicopter Avionics/ Electrical instructor with more than 30yrs in the business on various airframes (Cobra, Kiowa, Apache, Blackhawk, and Chinook’s). I think I can handle a car door.

Let us know what you find out. I’m very curious as electrical gremlins are the worst. Almost never the same thing twice. Good luck.
 

chuck s

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Picking the low hanging fruit first:

Anything plugged into any of the "cigarette lighter" power points? These are hot all the time and my GPS and radar detector pull enough power to kill the battery (sometimes) over a long weekend. My kid is an adult now but she sometimes left something plugged into the outlet in the middle seat.

Years ago -- make that decades -- I had a problem with a light in the trunk of a car which didn't go out when the lid was closed and was, of course, impossible to see. Not an issue with the Expedition but there may be hidden lights here too. My problem was detected by locking a 6 year old in the trunk for 3 seconds. :)

Sorry but that brings up a bad -- actually wonderful -- joke:

Who loves you more? Your wife or your dog? Lock both in the trunk and drive around for a few minutes. Open the lid and note who's happier to see you. :)

-- Chuck
 
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mchoudoir

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Did you ever figure out what was going on here? We have a 2020 Expedition Max that is doing the exact same thing. Ours isn’t always after sitting for a while either. We can drive to the store fine, park for 10 minutes, and it won’t start when we go to leave. It’s very frustrating. Most times, we can use the remote start to turn it on and it will start working again, which is even more bizarre.
 

SyndicateZ

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check the alternator/ battery charging when engine running?
 
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fordguy987

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Still having same issue. Went away for a few months as I had the rear liftgate and latch replaced due to inconsistently working. But it just came up again this morning when I moved the Expedtion out of the garage (using my key) then locked up. After I leff my wife attempted to start the car using her key and the same exact issue came up again. Dash flickering lights, brakes stiff, no start button function. She had to get out of the car, remote start it, re-enter, then meticulously press the start button without touching the brake pedal (it would turn car off if the brake pedal is depressed on this step) and it finished the startup just fine. Is there something with the remotes and programming that could be an issue?
 

Mr Big

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Still having same issue. Went away for a few months as I had the rear liftgate and latch replaced due to inconsistently working. But it just came up again this morning when I moved the Expedtion out of the garage (using my key) then locked up. After I leff my wife attempted to start the car using her key and the same exact issue came up again. Dash flickering lights, brakes stiff, no start button function. She had to get out of the car, remote start it, re-enter, then meticulously press the start button without touching the brake pedal (it would turn car off if the brake pedal is depressed on this step) and it finished the startup just fine. Is there something with the remotes and programming that could be an issue?
It could be your FOBs? Replace batteries, or stick the FOB in the console cupholder key FOB key slot hole, then try to start it.
 

keithstone

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Has anyone found any solutions to this? Our 2021 Expedition Max with 37,000 miles has been doing this for months. (I’ve inserted a link to a video of the lights flickering when pressing the brake pedal and won’t start as described in previous posts)
We’ve taken it to Ford twice and they weren’t able to find any issues. Last week the battery was replaced and the issue continued. We’ve replaced the FOB batteries, swapped FOBs and tried inserting them into the cup holder key slot and the issue continued.

Remote starting the vehicle sometimes works as a work around. We have also found that after waiting several minutes the car starts and operates without any issues. The problem seems to occur randomly.

https://drive.google.com/file/d/1Wkml971xTEISwyNcMbfq0enUKx6-MxiX/view?usp=drivesdk
 
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mindini36

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I just bought a 2020 limited with around 50K miles on it. LITERALLY. Got it home, it sat for a bit and is now doing the same thing!!! HELP
 

Mr Big

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I just bought a 2020 limited with around 50K miles on it. LITERALLY. Got it home, it sat for a bit and is now doing the same thing!!! HELP
Check the alternator. A diode can go bad and cause all sorts of issues, while still charging the battery.
One wreaked havoc on my ford excursion one time. the lights flickered; car bucked; and more. But it was still charging fine.
 

mindini36

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We pulled the battery. Had it tested (it was fine) put back in and it started. It would start with the remote start but would shit down when you pressed the brake to start normal. It is really bizarre. Had a 2018for years no issues.
 

Ugh_J

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The BCM reset thing as far as I know only resets the battery days in service stored variable. Nothing magic going on there. If you had to reset the BCM for the car to work, there'd be a whole bunch of people stuck as they don't know about that.
 

Rosalina

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Replaced the battery months ago. Could it still be the BCM?
The BCM reset thing as far as I know only resets the battery days in service stored variable. Nothing magic going on there. If you had to reset the BCM for the car to work, there'd be a whole bunch of people stuck as they don't know about that.

The shop I took it to replaced the starter. Freaking $500 they charged me for the part. Good lord. It starts now, but I’m afraid it’s going to do this to me again, because when Ford had the car, they said it was the battery, and it magically worked again.

I’m thinking disconnecting the battery and reconnecting it resets the computer or a bunch of sensors in the car, and that’s all that’s getting it to start again.

If it happens again, I’m just disconnecting the battery. Waiting 1 minute, reconnecting it, and see if it starts.

I feel like I just got ripped off a should’ve tried that myself.

We’ll see.
 

Ugh_J

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I think when you pull the battery, things temporarily reset to default "as-built" configuration and then gradually redetect via CANBUS signaling. I'm pretty sure I watched a video of someone whose truck wouldn't start because the tail light connector experience some water ingress, corroded, and started spewing noise into the wiring harness, causing a bunch of fault codes. This kinda stuff makes me want to pick up an old Willys WWII jeep with points ignition and zero electronics as a backup vehicle.
 

Fizzy

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The BCM reset thing as far as I know only resets the battery days in service stored variable. Nothing magic going on there. If you had to reset the BCM for the car to work, there'd be a whole bunch of people stuck as they don't know about that.

I suspect it's more than that. I've read here about people replacing their battery and electrical problems reappearing a short while later.

I've just assumed that the BCM tracks the aged performance characteristics of the battery. How much the max charge capacity has reduced by, how rapidly it charges, how rapidly it discharges, how it holds a charge. And it adapts the charging strategy and electrical load shedding strategy to match the battery as it ages. When you put a new battery in, it treats it like the old one.

The flip side to your point about "if you had to reset the BCM for the car to work..." is why would Ford put that procedure in the owners manual under the Replacing Battery section if it was unnecessary. Why even have a "battery days in service variable" in the first place.
 
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Fastcar

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Picking the low hanging fruit first:

Anything plugged into any of the "cigarette lighter" power points? These are hot all the time and my GPS and radar detector pull enough power to kill the battery (sometimes) over a long weekend. My kid is an adult now but she sometimes left something plugged into the outlet in the middle seat.

Years ago -- make that decades -- I had a problem with a light in the trunk of a car which didn't go out when the lid was closed and was, of course, impossible to see. Not an issue with the Expedition but there may be hidden lights here too. My problem was detected by locking a 6 year old in the trunk for 3 seconds. :)

Sorry but that brings up a bad -- actually wonderful -- joke:

Who loves you more? Your wife or your dog? Lock both in the trunk and drive around for a few minutes. Open the lid and note who's happier to see you. :)

-- Chuck
A radar detector ?? I've left my V1 plugged in for 5 days with no issue.
 

Boosted

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BMS Reset Procedure:

Push start button once, but don’t start.

Flash high beams 5 times

Press brake pedal 3 times

Watch battery light on dash and wait for it to flash

Start vehicle and the system should be reset.
 
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