DH03 : No Stall Pump

The number on the end of the error code refers to which pump is having the issue.  For example DH0#.

Pump failed the stall test; did not stall on either the upstroke or the downstroke.

• Replace inlet and outlet valve and seal for up and down strokes. 
• Replace piston and throat seals. 
• Replace rod and cylinder as necessary.