Hotpoint Cooktop Error Code F05

F05 indicates a fault with the NTC temperature sensor on the large induction hotplate, monitored via the ISI UART 1 channel at connector CN 03. The error has three subcodes: a short circuit in the NTC, an open circuit in the NTC, or the large induction hotplate not being detected as connected. The affected burner zone will be disabled until the fault is corrected.

When F05 is active, the large induction hotplate zone is disabled by the control board as a safety measure, so it will not heat. Other zones may continue to function depending on the cooktop model. You should not attempt to bypass this fault, as the NTC thermistor is a critical thermal protection component for the inductor.

Repair costs vary depending on the fault. If the issue is only a loose or dirty connector, there may be no parts cost and a minimal labor charge. If the NTC thermistor or inductor assembly requires replacement, parts alone can range from around 30 to 150 dollars or more, with labor adding to the total. A service call for diagnosis typically runs between 75 and 150 dollars before any parts are factored in.

Some cases of F05 can be resolved without parts by inspecting and reseating the CN 03 connector and cleaning any corroded contacts. However, if the NTC thermistor or wiring harness has failed, those components will need to be replaced. Working inside an induction cooktop involves capacitors that can hold dangerous charge even when unplugged, so technicians with appliance repair experience are strongly recommended for any internal inspection.

Powering the cooktop off at the circuit breaker and back on may temporarily clear the display, but F05 will return if the underlying fault with the NTC sensor or connector has not been resolved. A reset does not repair a failed thermistor, broken wire, or loose connector. The root cause must be diagnosed and corrected for the error to stay clear.