Bosch dishwasher - pump gone?

[Rustychain]

My 4 year old Bosch d/w hasn't been cleaning the dishes very well recently (eg. a residue is left behind on plates and things aren't that clean).

There's water in the machine and it gets nice and hot. What I did notice today was that the spray arms don't seem to be rotating very well - if I shut the door and run the cycle they don't appear to have moved (I tried this several times to make sure they hadn't just stoped in the same position!).

As the arms aren't striking anything, I wonder if the pump is going (blocked?), so there's not enough pressure to drive the arms around?

Thoughts/ideas appreciated.

 

[Diyisfun]

Dont know about your machine, but if my spray arms arnt working its because they are blocked. Have a look at yours.

 

[Rustychain]

Thanks for the suggestion - I've removed and cleaned the spray arms, and the associated pipework that feeds the arms. There were no blockages and the problems still exists. If it helps, it's the top spray arm that's not rotating very well, which I'm still assuming means low pressure...

Do pumps normally fail outright, or can their performance diminish as they begin to fail?

Thanks

 

[Sleepyhead]

Your machine may have a diverter valve fitted which switches between top and bottom spray arms. Possibly a stuck or failed diverter valve.