Dishwasher does not get dishes clean. I have found that the spray arm does not rotate nor does the telescoping spray tower go up. The rest seems fine. Fills runs and drains normally. Any suggestions?
Here is the parts breakdown
Replacement parts for WHIRLPOOL DP840CWDB5 | AppliancePartsPros.com
Could be just dirty filters or stuff stuck in the pump, the following should help you check/clean it.
https://secured.whirlpool.com/Service/SrvTechAdm.nsf/2cd44500d572193285256a45004fd9d6/56e33eb0e839a7fa85256a8e00510938/$FILE/4322430.pdf