Hi, everyone! I have a 2019 Ford Flex with 37,781 miles that was purchased in November 2019 with only 3 miles on it. I let my sister borrow it over the weekend to take my nephews on a summer vacation, and it ended up overheating on her 30 minutes before arriving at her destination. She said there was no other indication or behavior of the car to warn of anything wrong before the light indicator came on to show it was overheating. She immediately pulled into a Walmart lot, gave a video chat, and my teen son walked her through some basics. She purchased antifreeze, added it, checked the oil, and all seemed fine with the temperature. She drove about 10 more miles, then the car just stopped running; no warning indicators were displayed; it just stopped while she was driving on a turn-around and would no longer start. Someone pulled her to her hotel, and we drove out the following day and the car back by car trailer.

Some vehicle history: about 2 1/2 years ago, during the winter, the heater started acting up and would only heat when I accelerated. Once I'd come to a stop, it would blow the cold outside air. That following summer, the a/c went out. I had it fixed, but again, next winter, the heater would not heat unless I accelerated. I did some research and read it may be low on antifreeze, so I had my teen son add some, and that corrected the issue. Everything had been fine since then until this last weekend, when it overheated, and now it no longer wants to start up. I have uploaded a YouTube link to a video that shows what the vehicle does and the sound that occurs when we try to start it. At the end of the video, we show the dashboard. The light indicators show a check brake system, key programmed three keys total and no key detected, but the key fob is in the car, in my hand near the steering wheel. It's a push-button-to-start system; only one key fob was included when the vehicle was purchased and delivered to me. It was purchased from a Ford dealership out of state and delivered by a car carrier/freight service. I called a few times to try and get the second key fob, but with no luck. My son took a mechanic's course and received certification through our local college. He's still in high school but is able and willing to work on it if it's not too involved. He said, for example, that he would not want to work on it if it was the water pump that needed to be repaired due to how it is integrated into the motor, and he would hate to cause more issues. Any guidance or suggestions would be greatly appreciated!

https://youtube.com/shorts/J6CA4gGn4xs?si=6tY_HdCdBj_RhoJD

 

I have questions and maybe ideas.

Has your flex been regularly maintained? I would be suspicious of a water pump going out at 40K miles, unless you have a leak, or haven’t maintained vehicle.

Does it smell like pancakes?
Is there brown Burned staining where fluid has leaked?
What does the coolant and oil look like?
Coolant and oil levels?
Can the belly pan be removed? Is there oil or coolant staining on it, or where it’s parked/stored?
Has the vehicle ever entered limp home mode?
Have hoses and drain plugs been checked?
Does your flex have any remaining warranty?

As far as the key is concerned, the dealer can program additional keys for you. Owners manual should give direction on where to place the key, and the vehicle should start, provided the battery and engine are good.
This is from my owners manual, yours should show a similar procedure.




Can you gather the hexadecimal information from engineering test mode? With the engine off, press OKAY on the left of the steering wheel, press start to move the engine to “On” but not “run”. Continue holding OKAY button until engineering test mode comes up.

 

@Coconut_Worm Thank you for your suggestions! We’ve figured it out. We bought the car new in October 2019 and have always kept up with the maintenance. We were surprised that the water pump was the issue too, with such low mileage. Thankfully, it’s still covered under the powertrain warranty until October, so that’s a relief.

 

Unfortunately, when a vehicle overheats, depending on how high and how long, some problems will come up later. Suggest keeping a close eye on maintenance and performance. Problems like engine temp and oil consumption could appear later.