2020 Expedition occasionally doesn't start

[Jhlee730]

PAS engine disabled?
What is the perimeter sensor for the PAS do?
Maybe that triggers security sustem.
I.took it.to dealer and they wanted.to keep it.forever to try.and find the.problem

When they told.me.to.rent.a.car i got.pissed.and.left

 

[Deep8174]

Car not starting with no or weak ignition is almost always a battery issue.

 

[ROBERT BONNER]

There are lots of valid possibilities already listed. One that isn't listed is possible RF interference. Does the automatic unlock operate? If not and if everything off of the fob seems to be blocked, you could be experiencing RF interference. The fobs share a set of frequencies with those licensed to surveillance camera communication. So, if you vehicle is bombarded with this type of RF where it is parked, it can overload the FOB to vehicle communication and trigger an intentional anti-theft shutdown. I've had it happen on multiple vehicles. The temporary fix is to lift up one of the console cupholders where you will see a chamber to place the fob in. Put it in that chamber and the vehicle should start and run normally if that is the issue. Long term....don't park it there or eliminate the interference.

 

[Jhlee730]

Not it. Auto Unlock works. Kicker is, it does not display no key fob detected. Dash is blank, screen just says Ford.
Headlights flash when you push start

 

[Jhlee730]

Expedition acted up again dealer can’t locate issue unless it is in a failed state.
showed them a video that shows headlights and dash flickering plus one other that shows vehicle shutting off after opening and closing door

 

[duneslider]

I would still suggest a load test on the battery to see what sort of state it is in. Slightly weak batteries will cause all sorts of issues in modern cars.

 

[JasonH]

The easiest first step is to get the battery load tested. My Expedition behaved just like this when the carwash left accessories on and killed the battery the other day. On my Focus Electric, the built-in cellular connection was draining the 12V when the connection was poor and the vehicle was parked for an extended period, like in parking garages. Ford issued a software update to address the issue. Assuming the battery is ok, there may be something similar happening here.

 

[buckwheat-phd]

What do the logs say? I'm REALLY curious about this one

 

[buckwheat-phd]

It could well be the brake switch. There was a SB about this on certain Mercedes models that ran for years. Setting off the CE light, SRS light etc was also on the list. All for a $10.00 brake pedal switch

 

[buckwheat-phd]

Could also be as simple as a bad brake pedal switch.

Ditto