FOOT PEDAL REGULATOR STUCK "ON"
I dont know about the Singer, but I frequently get this on older Bernina models. The foot controller has a suppressor capacitor across the regulator and, on the Berninas, these capacitors fail with age, mainly because they were not specified with a high enough operating voltage for UK markets. Depending upon model, this component might be separately wired directly across the switch contacts or might be on a small circuit board. It is usually rated at 250V - I now routinely replace these with modern parts rated at 1000V and never have returns.
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