What Temperature Sensor Error Means
Four flashes of the Pots & Pans Wash light then one of the Normal Wash light means the temperature sensor is reading out of range. Viking's FDB451 dishwasher service manual (2012, page 13) gives three causes: wiring disconnected to the sensor, a defective sensor, and a defective control board.
Common Causes of Temperature Sensor Error
- Wiring to the temperature sensor disconnected
- Temperature sensor has failed
- Control board misreading a sound sensor
🔧 One Safe Check You Can Try
Nothing to check at the door. What you may notice is dishes coming out cooler than usual, or a sanitizing option that no longer completes, since the control has lost the reading it needs to confirm temperature has been reached.
⚠ Why You Shouldn't Go Further Than That
- Viking gives the temperature sensor a nominal 47 kilohm reading at named control-board terminals, which is a measurement rather than something visible at the plug.
- The sensor shares its connector block with the moisture sensor and the pressure sensor, so a plug disturbed while chasing one problem can create two more.
- Without a trustworthy temperature reading the control cannot confirm a sanitizing cycle actually sanitised, which matters more than the code's modest severity suggests.
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.