Dishwasher does not spray upper rack

[CPHokies]

Have a Kitchen Aid KUDK03CTSS (think made by Whirlpool), ~ 18 months old.  The upper deck sprayer has stopped spraying, water just dribbles.  The lower arm appears to still be cleaning, but also seems to clean poorly compared to last week.  I took apart the lower sprayer arm, but could not find a blockage for the upper sprayer arms.  Any ideas?  

Thanks

Model Number: KUDK03CTSS0

[kurtiusinteruppt]

you said you checked the lower sprayarm but your problem is most likely a clogged chopper screen- located deeper inside the sump. remove the sprayarm again and then start removing screws and sections ... you will know when you get there

[CPHokies]

Thanks, the food grinder was clogged.  Problem fixed!

[kurtiusinteruppt]

Good job! Don't forget that repair...
you will need it again