What Drain Error Means
One flash then five means that during a drain the pressure sensor output never fell to the empty level. Viking's FDB451 dishwasher service manual (2012, page 12) puts eight checks against this code, and the first five are all things a homeowner can look at before a technician is needed.
Common Causes of Drain Error
- Filters clogged with food debris
- Drain hose kinked, or missing its required high loop
- Disposal knockout plug never removed at installation
- Drain pump or pressure sensor has failed
🔧 One Safe Check You Can Try
Work through Viking's own list in order. Rinse the filters, check the drain hose behind the machine for a kink, confirm the hose rises into the high loop the installation guide calls for, make sure the machine sits level, and if the drain runs to a disposal, check the knockout plug was actually removed when it was fitted.
⚠ Why You Shouldn't Go Further Than That
- Once all five installation checks come back clean, what remains is the drain pump, the pressure sensor and the control board, and separating those three means readings taken at the board.
- A drain pump refitted with a fitting even slightly loose is a classic source of a slow leak that does not show for weeks.
- Water left standing in the tub while the cause is hunted goes stagnant and reaches the door seal, adding a smell that outlasts the repair.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.

