Bottom spray arm on Bosch dishwasher not spinning
A few weeks ago we noticed the bottom drawer of the dishwasher wasn’t cleaning like the top and very quickly discovered the spray arm at the bottom wasn’t spinning.
As far as I can tell, the spray arm is fine; no blockages and no cracks.
I have run the dishwasher with everything removed and water is coming out of the hole that joins to the top spray arm but nothing at the bottom one.
The model is SMV40C00/GB and is over 10 years old, so I appreciate it may be time for a new one. However, before I make that decision, is there anything I can do that may resolve it?
EDIT: Neither arm is actually spinning, although water is flowing from the top arm.