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Car died and wouldn’t go over 1000Rpm or 5mph

TyphoonFiST

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#21
Where is the PCM located?

Also does anyone have a wiring diagram of chassis grounding locations. I’m curious if the PCM and stability control module share a common ground.
Its right near the battery....can miss it....[biggrin]
 


koozy

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#25
does anyone have a wiring diagram of chassis grounding locations. I’m curious if the PCM and stability control module share a common ground.
It should go without saying, but hopefully you checked all of your fuses in all fuse boxes. Fyi, fuses don't always burn out in the middle.
 


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zanethan

zanethan

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Thread Starter #26
I haven’t checked every fuse. If a fuse did blow, how would it be possible that it would start acting normally again, and largely ever since?
 


koozy

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#27
I haven’t checked every fuse. If a fuse did blow, how would it be possible that it would start acting normally again, and largely ever since?
The issue you're experiencing seems to be a gremlin, checking the fuses just covers your bases, like checking the battery. You got to start somewhere. It's a process of elimination. You don't have much for us to go on except weird symptoms.
 


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zanethan

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Thread Starter #28
The issue you're experiencing seems to be a gremlin, checking the fuses just covers your bases, like checking the battery. You got to start somewhere. It's a process of elimination. You don't have much for us to go on except weird symptoms.
Totally agree. I guess it never hurts to double check. Looks like Saturday is gonna be a fun one!
 


Intuit

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#29
List the descriptions for each of the codes.

You may find that they all have a particular wire harness in common. At that point it may dawn on you that a particular harness was disturbed or unplugged when changing out a stock part.
 


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zanethan

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Well the plot thickens. It did it again tonight coming back from some friends. This time I couldn’t get it to restart for a solid 10 minutes. Out of frustration I tried starting it again while pushing the brake and presto fired right up. It stalled a few more times and would not turn over until I also pressed the brake while starting. Got it back home and of course, all is normal. I do have a check engine light now P2610 (ECU/PCU off timing). I also tried unplugging both the sensors to see if that would trigger the symptoms but it didn’t. What is semi alarming is that even with both sensors u plugged there were NO dash warning lights but maybe those are just tail light switches. So this has me thinking it’s brake system related in someway shape or form. Anyone have any pointers from here??
 


maestromaestro

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#31
If it were an automatic, that'd be one thing. Pressing the brake - I wonder if the pedal touched something loose? On the other hand, is there a short of some kind that involves the braking circuit?

Have you tried unplugging the ECU harnesses?
 


TyphoonFiST

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Well the plot thickens. It did it again tonight coming back from some friends. This time I couldn’t get it to restart for a solid 10 minutes. Out of frustration I tried starting it again while pushing the brake and presto fired right up. It stalled a few more times and would not turn over until I also pressed the brake while starting. Got it back home and of course, all is normal. I do have a check engine light now P2610 (ECU/PCU off timing). I also tried unplugging both the sensors to see if that would trigger the symptoms but it didn’t. What is semi alarming is that even with both sensors u plugged there were NO dash warning lights but maybe those are just tail light switches. So this has me thinking it’s brake system related in someway shape or form. Anyone have any pointers from here??
Call Ford and find out if there is a TSB for that code... it has to do with the PCM/ECM engine timer....it could need to be flashed or replaced. It could also be a CKP/Cranshaft position sensor failing intermittently. You would have to drive the vehicle with live feed data recording and see if you can watch the CKP fall on its face. These are my thoughts....




Sent from my SM-N950U1 using Tapatalk
 


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#33
Fix the p0504 Brake switch/p2127 accelerator pedal position sensor first. Everything else should be fine after. Your car seems to be in gas plus brake mode (what it feels like after a few seconds of left foot braking) because it can no longer sense if you are touching the brake pedal and Ford doesn't want you to PriusCop yourself into a wall while holding both the brake and gas.

That's my GUESS anyways....
 


maestromaestro

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#34
Fix the p0504 Brake switch/p2127 accelerator pedal position sensor first. Everything else should be fine after. Your car seems to be in gas plus brake mode (what it feels like after a few seconds of left foot braking) because it can no longer sense if you are touching the brake pedal and Ford doesn't want you to PriusCop yourself into a wall while holding both the brake and gas.

That's my GUESS anyways....
It wasn't a Prius - a Lexus. And he never actually pressed the brakes. Hit a ditch.

I like your suggestion tho. [emoji4]
 


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zanethan

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Thread Starter #36
Fix the p0504 Brake switch/p2127 accelerator pedal position sensor first. Everything else should be fine after. Your car seems to be in gas plus brake mode (what it feels like after a few seconds of left foot braking) because it can no longer sense if you are touching the brake pedal and Ford doesn't want you to PriusCop yourself into a wall while holding both the brake and gas.

That's my GUESS anyways....
Where would I start with the brake switch code? What sensor would trigger that?
 


D1JL

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#37
Where would I start with the brake switch code? What sensor would trigger that?
You could just enter P0504 into your internet search box.

If you are trying to fix your own car, I would suggest first buying a service manual.
Maybe you might need some specialized electronic tools, like a multimeter or for code timing issues, an oscilloscope.

Sometimes it may be best to seek professional help, it may even be cheaper in the long run.

I know that many here have and will try to help you but it is almost impossible to fix a car by remote control.
 


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zanethan

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Thread Starter #38
You could just enter P0504 into your internet search box.

If you are trying to fix your own car, I would suggest first buying a service manual.
Maybe you might need some specialized electronic tools, like a multimeter or for code timing issues, an oscilloscope.

Sometimes it may be best to seek professional help, it may even be cheaper in the long run.

I know that many here have and will try to help you but it is almost impossible to fix a car by remote control.
Do you seriously think I didn’t start with searching that code? In fact that’s where I started. Hardly any other Fiesta owners have encountered that code (or at least few have posted about it) and since it’s a general power train code I was seeing if ‘blurred’ had a more specific place to start narrowing it down. I’m not trying to be lazy and leech off of members but I thought the point of this forum was to collectively gather experiences and issues related to our platform. I guess I’m just the first Fiesta owner to experience this exact issue. Lucky me!

Car has been sent to the dealer at this point as yes, I agree, diagnosing this is above my mechanical abilities.

I’m not sure why I’m drawing your ire I’m just trying to narrow down what others are suggesting and put my threads in the proper sub forums for future members that experience this issue.

I must admit I expect more out of a moderator on this forum especially in regards to a productive and active member of this community for over 2 years. Sure, I certainly wasn’t the nicest during the ProDigit/MeLee debacle but I’ve since apologized for that and stayed well out of his threads.
 


D1JL

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#39
I don't know why you think I am the bad guy here.

I did shut down the other thread as it was not necessary to have the same thing in two locations (my job here).

However I did read the thread and saw that you were getting executant suggestions.
But your last comment was what I was referring to.

"Where would I start with the brake switch code? What sensor would trigger that?"

So I suggested that you look it up on the internet because it is there (I just looked it up).
And then tried to point out that the cost of some tools (I know, I have them) may be more than taking it to a shop.

My last comment was based on my own personal experience.
As a retired ASE Master Tech. I know how hard it is to repair a car by remote.
I also know that intermittent problems are the worst to diagnose.

So in all, I was just trying to help you.
Maybe I should stop doing that.
I didn't see you lashing out at anyone else's suggestions.
But then I am sure that you are frustrated with the problems you are having.


Good Luck
 


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zanethan

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Thread Starter #40
I don't know why you think I am the bad guy here.

I did shut down the other thread as it was not necessary to have the same thing in two locations (my job here).

However I did read the thread and saw that you were getting executant suggestions.
But your last comment was what I was referring to.

"Where would I start with the brake switch code? What sensor would trigger that?"

So I suggested that you look it up on the internet because it is there (I just looked it up).
And then tried to point out that the cost of some tools (I know, I have them) may be more than taking it to a shop.

My last comment was based on my own personal experience.
As a retired ASE Master Tech. I know how hard it is to repair a car by remote.
I also know that intermittent problems are the worst to diagnose.

So in all, I was just trying to help you.
Maybe I should stop doing that.
I didn't see you lashing out at anyone else's suggestions.
But then I am sure that you are frustrated with the problems you are having.


Good Luck
Ah the issues of trying to decipher inflection via text. Your comment of ‘Or you could just search the code in the internet box’. Came off as smart a**y to me but you clearly didn’t intend for it to have been meant in that way.

My apologies for lashing out I just thought you were accusing me of being lazy and not wanting to do any research which I can assure you I’m not trying to do.

As I said I dropped it off at the dealer since it’s happening with the factory tune and throwing some codes again so hopefully it’s something as easy as a faulty throttle position sensor.

Again my apologies for lashing out I put my own emotion into your text.
 


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