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U0131 code - Another damn ECU problem

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Location
Bellflower, CA, USA
#1
Here we are again .... car today was running fine after ECU / PCM issue a month ago.

Today - took car for drive - nothing to crazy - just a lunch at the park kind of day ... god damn car would not start ( just like before ) - push button ( ignition on / push again nothing ) . Had an OBD reader in glove box , ran code check.

It read out same issue as what dealer said a month ago - “ lost communication with PCSM “ code U0131 . Any ideas ? Why this crap is happening so often. Paying towing on that car is killing me.

Dont want to run a lemon law on it but ... hell what gives with the ECU. ?

Help
 


TyphoonFiST

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#2
Did the stealership replace the ECM/ PCM? Or did they re-flash it? Did they use a New part or Re-man part?

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OP
Darkflamedesign
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Location
Bellflower, CA, USA
Thread Starter #3
Who knows ... blew up their phone and left message at service center ( closed today sunday ) . Hopefully getting call tomorrow ...

Gonna ask those questions- thanks for that.
Just getting frustrated about vehicle.
 


TyphoonFiST

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#4
Who knows ... blew up their phone and left message at service center ( closed today sunday ) . Hopefully getting call tomorrow ...

Gonna ask those questions- thanks for that.
Just getting frustrated about vehicle.
Keep us all up to date!

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Rocketst

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#5
Problem could be a faulty connection. Either connection is not tight enough or the harness connection is bad. You say it's been driving fine, what changed?

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OP
Darkflamedesign
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Location
Bellflower, CA, USA
Thread Starter #6
Problem could be a faulty connection. Either connection is not tight enough or the harness connection is bad. You say it's been driving fine, what changed?

Sent from my IN2019 using Tapatalk
Actually was only in about 3-4 weeks of LAST ECU “ repair “ and was driving the miles i assumed computer needed to re-learn. I only put maybe about 150 miles of so over that time and it was another weekend to get the car out and about. Made some errands and no issue ... then i parked one last time for lunch and car stopped starting.

No dash faults ( no wrench or engine light )
Normal ignition light up - but NOTHING-after push button start. So i ran the OBD i had in glove compartment- then got only one code ( U0131 ) .

Same bullsh&$ as before - exactly the same thing it was serviced for. I heard fiestas also suffer from crappy ground points too but don’t know ... waiting for service department to call me back.
 


OP
Darkflamedesign
Messages
47
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Location
Bellflower, CA, USA
Thread Starter #7
Ok ..... The following update should be FYI .

I figured out where the “ fault “ lay in this ECU issue. Down at driver side footwell panel , there under panel is a portion of the main harness .... connectors and such.

I knew that ignition wiring runs thru there so I popped panel on a hunch .
I looked at those kind of cheaply looking harness connectors and decided to apply pressure on them to ensure proper seating ..... after that , it started .

No faults
No dash lights ( engine )
No codes either.

Should have taken pic of what I’m talking about ( will do that later ).
CAR runs strong and no issues. The more I look at ford’s wiring harness, it becomes rather clear they are a bit wonky. I could see why there would be pin / connection failures.

But now all good.
 




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