Mazda6 ABS/ESP - C0044 Brake Pressure Sensor 'A'

I see this topic has been up in 2012. I hope that in the time up to now have given someone some more experience.

My precious Mazda 6 2009 2,2 MZR-CD 125 hk shows code C0044A - Break Pressure sensor A.

My local (and trustworthy) mechanic has changed the complete ABS unit from a similar motor. The break pedal switch has also been changed. When he starts up the car after repair the ESP light turns off before it lights up again. The issue is still there.
Is the solution to refurbish the original ABS unit or is the non repairing change of unit a proof that something else is wrong?

Any other suggestions?

Please help me save my beloved Mazda from the scrapyard.

A little history if this can be to any help...My Mazda has in all my time eaten breaks. Even disks has been changed many times. When they came to a certain point of wearing...The rest vanished in no time. To prevent this from happening we ordered a change of calipers. After this there has been a couple of extra light on in my dash. ESP and DSC.

Thank you for any help!