What Fault 5 Means
Fault 5 is filed against the FC sensor, the probe ActiveSmart relies on to read the freezer compartment. Its resistance has gone past 45,000 ohms, which F&P's problem table treats as an open circuit somewhere between the thermistor bead and the power module, so the figure reaching the board is no longer a temperature at all.
Common Causes of Fault 5
- The thermistor bead has gone open circuit with age
- A break or pinch in the sensor lead where it passes through the cabinet
- The sensor plug backed part-way out of its socket on the power module
🔧 One Safe Check You Can Try
There is nothing to measure without a meter, but keep a note of how the freezer side has behaved since the alarm began - drifting warmer, running colder, or unchanged - because that pattern tells the technician whether the cabinet is still being controlled sensibly.
⚠ Why You Shouldn't Go Further Than That
- Isolate the refrigerator at the outlet before anything else, because the sensor loom is bundled with the mains-voltage feed to the compressor and the two are hard to tell apart by color alone.
- A resistance reading only means something when it is taken at the right ambient and compared against the published curve, so a number read out of context leads straight to the wrong part.
- Freezer-side sensors are routed close to the evaporator circuit, where a slip with a screwdriver turns a small sensor job into a refrigerant repair.
- Sensor leads are cut to length at the factory; a replacement that is pulled taut to reach will chafe through at the grommet within a season.
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.