VSA, ABS, Brake indicator on with code 81-1

The VSA, ABS & Brake System Indicator light came on in my 7th gen 2.2 cdti. Switched off and on and they went away.

The next time I used the car the lights came on again and wouldn't clear. Testing with the ODB socket pins 4 & 9 connected gave B1170 with I think is Gauge control module lost communication with the VSA modulator control unit.

My local garage (who had replaced the VSA unit in December) used their Snap-on tester which showed
54-1 Safety relay - faulty electric circuit 1141833888
81-1 ABS hydraulic unit - faulty electric circuit 1896808608
84-1 ESP sensor unit - calibration faulty or not carried out 1947140256
These were cleared and only the 81-1 returned.

The multipin connector to the ABS/VSA unit has been checked that power is getting to it. The pin layout on this connector from the 3980 page Accord 03-06 pdf does not match what's in the car, but one of the pins has 12v.

The plan is to get an auto-electrician to investigate but any other suggestions would be welcome.

Update

The auto electrician has confirmed that there's an electrical fault in the ABS/VSA unit and BBA Reman (via UPS) are collecting it on Monday for (another) repair under warranty. I'll post again when/if it's resolved.

The repaired unit was returned today (Friday) with no explanation of what the fault was. After installation all warning lights are out and the error codes have been cleared.