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Brake Booster Pressure Sensor Circuit Low Short To Ground

EJFocus
EJFocus
in Ford Focus Club

Featured Replies

Hello all, I am new to ford and this forum so apologies if this is in the wrong place etc. My car (2012 ford focus 1.6L ecoboost) has been behaving strangely lately with random ABS errors the stop start refusing to work amongst a strange sound and feeling when driving at low speed or breaking. 

My car is still under warranty from the dealer I purchased it from so am keen to get this sorted during the warranty period, especially if major otherwise am happy to do myself or get someone locally to do that for me. 

I initially believed that these issues may have been  caused by the vehicle having an aging battery, so I ordered a replacement, reset bms and cleared codes. Almost all of them didn't return apart from the following: 

P0557 - Brake Booster Pressure Sensor Circuit Low

Additional Fault Symptom (:11):
 - Circuit Short To Ground

Status (-2F):
 - DTC Present at Time of Request
 - Malfunction Indicator Lamp is Off for this DTC

I believe  I may have wasted my time and money by  replacing the battery, however its too soon to know for sure.

From some research I believe that it is this DTC that could be causing my stop start not to work as well, not that this bothers me massively. 

Does anyone have any tips or suggestions for how I can begin to diagnose and fix this, I would really appreciate any help.

 

Thanks in advance, Ethan
 

  • Quote


    https://autonevod.com/obd2-codes/p0557

     

    look down the page lots of info

  • Quote
    • 4 weeks later...
    • Author

    For anyone wondering in the future, it did turn out to be the sensor itself. £40 and 3 mins later fitted and working. Stop start now fully functional as well. 

  • Quote
    • Like 2
    • 2 months later...
    On 6/13/2024 at 7:43 PM, EJFocus said:

    For anyone wondering in the future, it did turn out to be the sensor itself. £40 and 3 mins later fitted and working. Stop start now fully functional as well. 

    Have exactly same fault on my 2011 mk3 1.6 TDCI. Where is the sensor located - can't find it in Haynes or on-line. Also do you have a link to the part you used. TIA

  • Quote
    On 6/13/2024 at 7:43 PM, EJFocus said:

    Stop start now fully functional as well

    Late reply I know but it'll be the new battery and BMS reset that got it working.

  • Quote

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