What Pressure Sensor Disconnect Error Means
Two flashes of the Pots & Pans Wash light then one of the Normal Wash light means the pressure sensor is reading out of its normal range on the low side. Viking's FDB451 dishwasher service manual (2012, page 12) has the technician verify the sensor is properly connected before condemning either it or its harness.
Common Causes of Pressure Sensor Disconnect Error
- Pressure sensor connector unseated at the control board
- Sensor harness damaged
- Pressure sensor has failed
🔧 One Safe Check You Can Try
Nothing can be reached from the front. What is worth understanding is how central this part is: the pressure sensor is how this generation of Viking dishwasher knows how much water is in the tub, so while it is disconnected the machine has no fill or drain reference at all.
⚠ Why You Shouldn't Go Further Than That
- Viking specifies 5 volts DC into the sensor and 0.5 to 3.5 volts DC back out of it, so proving it means live readings at named board pins.
- The sensor reads the sump through a small air line, and a line pinched or wetted during reassembly returns figures that look exactly like a failed sensor.
- Fill, drain, level and siphon codes all lean on this one sensor, so a wrong call here comes back later wearing a different code.
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.