My United Kingdom Neff S5443 dishwasher spinning arms (x2) have
stopped spinning there must be a pressure drop.
There is mains water and there is no blockage in the mains water
supply I have checked.
Also the alarm sounding the end of the program has also stopped
working at the very same time.

The drainage pump is working but no rushing water sounds after it has
drained as before.
Is there a solution and if so if there some working instructions on
dismantling I am very well equipped DIR with an  engineering
background but need advice.

if it is the spinning arm that stop rotating then most likely the
motor have gone bad. Majority of times when motor goes bad, it is
caused by deterioration of insulated coil and some connection become
shorted within stator coil(outter coil of the motor). This cause
reduction in magnetic flux and torque is reduced. When there is
significant deterioration then the stator doesnt induce enough flux to
rotate the arm. Only economical solution is to replace the motor.

I recently had the same issue, the lower arm worked,the top one
didn't. In my case the pump cover was cracked, causing a loss of
pressure. As the previous reply said, make sure your pump runs, in
both directions - usually they run forward to pump water around for
the wash cycle, then reverse to pump the water out. Also check for a
blockage in the tube going to the washer arm. (This assumes that it is
filling with enough water, open it mid-cycle to verify...) There are
sites with parts diagrams and tips, and you can get the replacement
parts there also. Sometimes your local shops can offer advice as well.
Try: http://applianceguru.com/ Good Luck!