Indesit Dryer Error Code F15

The F15 error code on an Indesit dryer indicates that the upper heating element is active when the control system has not commanded it to be on. This is a detection fault rather than a simple element failure: the control board is reading current flow or heat output from the upper element circuit at a time when it should be de-energized. The dryer's control module continuously monitors element status, and when it detects an unexpected active state in the upper element, it triggers F15 to prevent overheating or a potential fire hazard.

The most likely starting point for diagnosis is connector J4 on the control module. A loose, corroded, or partially seated J4 connector can cause false voltage signals to be interpreted by the board as element activity. This connection carries switching signals between the control board and the heating circuit, so any intermittent contact can produce misleading readings that trigger the fault without an actual element malfunction.

If the J4 connector is secure and in good condition, the fault typically points to a relay on the control board that has failed in the closed position, keeping the upper element circuit energized even when the board attempts to open it. A shorted triac or relay contact is a common failure mode. Less commonly, wiring insulation breakdown between the element circuit and a live conductor can create a leakage path that mimics an active element. Thorough inspection of the wiring harness, the relay output on the board, and the element itself is needed to isolate the root cause.