Field pattern: Thermador ExtraLow burner 'turns itself off and on' (normal XLO cycling, not a bad valve or spark module)

On ExtraLow (XLO) burners the flame is designed to cycle on and off automatically inside the XLO range; higher XLO settings keep the flame on longer. The wrong turn is treating that cycling as a fault. A real fault is a burner that will not light, will not stay lit at normal settings, or does not cycle at all in XLO.

Cross-checked ~20 min easyBrands: Thermador

Before you start

Gas valves, gas pressure and burner orifices are not field-adjusted in this guide: refer to a licensed gas technician or factory service
If you smell gas, turn burners off, ventilate, do not operate switches and have the customer call the gas utility

Diagnostic steps

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