Automatic acceleration - scary situation

[NewGuy]

While driving the car, it threw a “1-pedal drive fault” and “Service vehicle soon”. The FordPass app shows “power train malfunction/ reduced power”.

While driving, the car automatically accelerates continuously, unless you press the brake pedal. Starting from 0 it got up to 30before I stopped it, so I’m not sure how fast it would let itself go. The brake pedal makes it slow/stop but it’s pretty abrupt.

Oddly, it’s basically the exact opposite of one-pedal mode. In one-pedal the default is to stop, and you press the accelerator to go, release to stop. In this, the default is to go, and you press the brake to slow and release to accelerate.

Oh, and the accelerator pedal does nothing; nothing at all.

Will call the dealer tomorrow, I have it on video to show them, but has anyone heard of this?

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[Mach-Lee]

Yes, it says “1-Pedal Drive Fault, press brake pedal to reduce speed” so there’s your warning about needing to press the brake to slow down.

Shut the car off, walk away for 10 minutes, and try driving it again.

 

[NewGuy]

Yes, it says “1-Pedal Drive Fault, press brake pedal to reduce speed” so there’s your warning about needing to press the brake to slow down.

Shut the car off, walk away for 10 minutes, and try driving it again.

But it doesn’t say “if you don’t press the brake pedal the car will continue to accelerate on its own”.

 

[Mach-Lee]

But it doesn’t say “if you don’t press the brake pedal the car will continue to accelerate on its own”.

It won’t accelerate past 4 mph with your foot off the pedals unless you are going down hill. It’s more correct to say it started coasting.

 

[NewGuy]

It won’t accelerate past 4 mph with your foot off the pedals unless you are going down hill. It’s more correct to say it started coasting.

Re-read my first post. It went from a stop to 30 and was still climbing. This wasn’t a one time blip in speed, this is how I had to drive it home. I have it on video.

It wasn’t floored/max acceleration, but steadily increasing and the accelerator did nothing.

 

[Mach-Lee]

Re-read my first post. It went from a stop to 30 and was still climbing. This wasn’t a one time blip in speed, this is how I had to drive it home. I have it on video.

It wasn’t floored/max acceleration, but steadily increasing and the accelerator did nothing.

I’d have to know your codes to be sure, but if the throttle pedal did not vary the torque whatsoever after the fault, and you had stopped several times, then that’s a FMEA mode for a failed accelerator pedal or failed motor control. It’s effectively a limp mode that allows you to drive the vehicle in an emergency condition rather than being completely stranded.

 

[breeves002]

If you need to slow the car down hit the brake pedal like it tells you to. Problem solved.

 

[NewGuy]

I think there was a post asking for more specifics about if my feet were on the pedals, but it looks like it was deleted. Foot on the brake pedal to hold the car at a stop. Release the brake pedal and don’t touch anything else, car begins accelerating, and continues accelerating. I let it get as fast as 30mph before I hit the brake as I was in a neighborhood and there was a stop sign. I hit the brake to slow and stop. Then repeat everything to get back up to speed to keep driving for the rest of the drive home.

I’d have to know your codes to be sure, but if the throttle pedal did not vary the torque whatsoever after the fault, and you had stopped several times, then that’s a FMEA mode for a failed accelerator pedal or failed motor control. It’s effectively a limp mode that allows you to drive the vehicle in an emergency condition rather than being completely stranded.

Ah; if that’s a mode that sounds like it’s it. Is the only way to pull codes with a scanner?

If you need to slow the car down hit the brake pedal like it tells you to. Problem solved.

I assume you’re joking, but it’s like driving a car with the gas pedal halfway down. I did check to see if the pedal was indeed stuck, and tried to pull it up with my foot, but it didn’t move.

 

[Mach-Lee]

I think there was a post asking for more specifics about if my feet were on the pedals, but it looks like it was deleted. Foot on the brake pedal to hold the car at a stop. Release the brake pedal and don’t touch anything else, car begins accelerating, and continues accelerating. I let it get as fast as 30mph before I hit the brake as I was in a neighborhood and there was a stop sign. I hit the brake to slow and stop. Then repeat everything to get back up to speed to keep driving for the rest of the drive home.





Ah; if that’s a mode that sounds like it’s it. Is the only way to pull codes with a scanner?



I assume you’re joking, but it’s like driving a car with the gas pedal halfway down. I did check to see if the pedal was indeed stuck, and tried to pull it up with my foot, but it didn’t move.

Thanks for the extra details, that would be a fixed torque limp mode most likely. You can message me your VIN, I can check what’s up.

 

[VaporTrails]

Only you can determine if it feels safe enough to drive to a dealer. I would reboot the car (by removing the negative battery lead). While the battery is isolated, look at the acceleration pedal very closely to observe if it seems to have full travel and nothing is hanging or losely attached. It seems unlikely to me that the software would allow the car to accelerate without a series of valid throttle conditions. So the car thinks the throttle mechanism is fine and the reading is valid.

 

[Glen Boise]

Were you on cruise control? I have run into situations while on cruise control and had just left a construction zone with a lower speed limit, the cruise control would jump up the speed 20 mph or more past what I had programed it previously before reaching the construction zone. Found there is an adjustment possible reducing the jump in speed in the cruise control controls in the car programing area.

 

[NewGuy]

Were you on cruise control? I have run into situations while on cruise control and had just left a construction zone with a lower speed limit, the cruise control would jump up the speed 20 mph or more past what I had programed it previously before reaching the construction zone. Found there is an adjustment possible reducing the jump in speed in the cruise control controls in the car programing area.

Not on cruise control. It would re-accelerate after hitting the brakes.

 

[Mach-Lee]

You had a P061A code in the PCM for internal torque monitor performance. This means there was an internal torque calculation error and failure mode was entered. This is most likely a software glitch. My guess is the car will drive fine tomorrow, but you should have the dealer document it.

 

[fneild48]

Were you on cruise control? I have run into situations while on cruise control and had just left a construction zone with a lower speed limit, the cruise control would jump up the speed 20 mph or more past what I had programed it previously before reaching the construction zone. Found there is an adjustment possible reducing the jump in speed in the cruise control controls in the car programing area.

Re-read my first post. It went from a stop to 30 and was still climbing. This wasn’t a one time blip in speed, this is how I had to drive it home. I have it on video.

It wasn’t floored/max acceleration, but steadily increasing and the accelerator did nothing.

Same thing happen to me about a year ago. Stopped at the super market and when I came back every thing worked fine. Never had the problem again.

 

[Mjtee2]

Not sure if this is related but we have recently had both of our MME’s (2021 & 2023) spontaneously accelerate around 20 MPH past our settings on autopilot!

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