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9 Posts
Discussion Starter · #1 ·
Hello hello!
I purchased my 2020 ecoboost premium last week and on the way home it threw two errors.
Pre-Collision Assist not Available and Hill Start Assist Warning

No wrench icon appeared on the dash.
I texted the dealer and he said to bring it in the next morning.
They asked me all the things they could to see if it was my fault. Like if I slammed on the brakes or something.
Nope none of that.

It happened as recently as driving it to them that morning. Braking at a stoplight. No car in front of me.

They drove it, a few times, got it to go off. Checked for codes, NO CODES.
How does a car throw errors or faults and not record a fault in the codes or history?

After over an hour, they reset the computer and said to "see if it comes back" and sent me on my way.
It happened on my way home of course.

I have read that there could be debris in the bumper?
Or maybe the sensor itself needs replacement?

In ALL the threads I've found, nobody who started the thread, finishes with a comment of what if anything fixed it.

Has ANYONE seen this and fixed it to make it go away forever?
The pre-collision is a concern, safety features failing is not cool and when that gets thrown, it disabled Cruise Control entirely
an ironic twist of fate since I like using Adaptive Cruise Control on the highway.

I have pinned down HOW to throw the error.
You simply have to make a complete stop.
We don't really register it in our brains as we're so used to it, but we very often coast to stoplights and never actually make a complete stop.
Between my mom's house in the suburbs to my house in the city, I can go 80% of that trip without doing a full, complete stop.
If it doesn't throw on the first stop it always does by the second.

Anyway, I'm calling the dealership today to figure out when I can drop it off and get a rental.
I don't want it back until it's fixed.


9 Posts
Discussion Starter · #3 ·
Thanks for the post. PLEASE use this as an opportunity to be the guy that posts the solution!! Thanks again and good luck with getting it fixed right the first time as well as quickly. .
Absolutely! I'll be very specific about what fixes it or if it's never fixed.... I'm 7 days into ownership, in MN I can serve them a written request within 30 days to cancel the financing and return the vehicle.
They have 23 days to sort it out.
If they don't I'll be forced to walk. I don't care if the entire brake system and abs or safety system or sensors have to be replaced.
Buying a car and having sensors throw 2 very specific errors every day (and disable features of the car) since you bought it, is unacceptable.

I am curious what happens with the trade-in I made though.
Whether I get that back, or they pay me outright for what was put against the financing ($16k)

I mean, I'm hopeful they get this sorted. My salesman was nice enough he said if the service dept thinks it's a 1-day fix, he'd let me borrow his car as a rental.
I would feel bad returning it, just want it to work! I don't think that's too much to ask :)

I've just been stressing over this so much and losing sleep wondering if I made a mistake going with a Ford. It's so fun, but broken since day one 馃槶
Sorry for the rant 馃槄 ugh

9 Posts
Discussion Starter · #7 ·
I had these same two issues earlier this year during a snow storm. The camera was covered up with snow, told me to clean the camera / sensor - I ignored it and then it tripped the pre collision and hill assist errors. As soon as I turned my car off (without cleaning anything off!) things went back to normal.

I imagine it is just flawed logic in the Ford Pilot360 software. Something I wish to turn off.

But it has not happened since.
I believe the camera for the pre collision assist is in the windshield center area below where the rear-view mirror is attached. There is a black box attached to the inside of windshield below mirror that houses the camera and if its blocked or has something obstructing its view it will set those faults. Not sure if hill assist is tied into the same camera but it is possible.

Thanks for the messages!
There is no snow on the sensor or any other obstructions in front of the camera.

I've made an effort to narrow down what triggers it.
It usually happens at stop signs, when I come to a complete stop.
OR if I am braking with decent pressure. Not an emergency braking situation by any means, the ABS isn't kicking in for example.
Just a solid and consistent amount of pressure while braking will throw the pre-collision and sometimes, maybe 80% of the time, it also throws the hill assist.

Interestingly the Hill Assist one says " The ABS module has a battery voltage fault" no idea what would have to be replaced in order to fix that.
Any faults/erors with the ABS to be honest is quite concerning. The other says yes to clean debris and if it keeps coming back to take it to an authorized dealer.

Service is scheduled for Monday and I'll be getting a rental.
I'm nervous they won't get it fixed and just give it back for me to see the error again and I'll have to keep coming back.
We'll see what happens.

Will update this thread on Monday or whenever they give it back to me!

9 Posts
Discussion Starter · #10 ·

You pretty much nailed it Buldawg76!

Got the car back today (dropped it off monday and today is wednesday)

The mechanic notes:
test drove working ok. No warning lights.
Ran self test and getting code c0040 that keeps coming back.
did pinpoint ac for this.
Did not come to conclusion but suspect brake pedal position switch. replaced switch and test drove and working ok at this time.

I did get a ford connect alert while they had it that they did trigger the warning messages while test driving which I'm glad they were able to trigger.

Drove it home today and it didn't error at all so I'm hopeful it's fixed for good.

The real test will be when it gets hot again, it seemed to throw it in hotter temps, the day I dropped it off for example was in the 60's and it didn't throw them in ways I was typically able to reproduce them easily.

But that's it so far! A faulty Brake Pedal Switch.
I'll update the thread if it comes back. Crossing my fingers that it doesn't

9 Posts
Discussion Starter · #12 ·
Thats interesting that the brake pedal switch could stop the pre collision assist and hill assist from working but still function enough to allow the car to start unless there are two separate switches at the brake pedal. Interesting for sure and hope the switch is the issue and your problem is fixed.

Yea maybe there are two switches, I'm not sure. It sort of made sense because if I'd push down on the brake hard enough it would throw the fault, but not bring up the Wrench icon meaning service immediately... Maybe the switch had a weak connection to the rest of the system (hence the low voltage message) which would be exacerbated by warmer weather as heat expands things of course making the connection loose/worse.

Quite strange/interesting indeed.
Hope this saga is over, and I don't have another for a while :)

Driving it home was a joy
Love driving this lil ecoboost 'stang!
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