A replacement ceiling fan switch was purchased from Home Depot for a three speed Hampton Bay (Marco Polo) ceiling fan. Both the old and new switch had the same wire colors (L-black 1-grey 2-brown 3-purple) and the new switch was inserted according to the colors. The fan will not turn off now. Is the new switch defective. I have means to check progressive continuity.

No, it's probably not the right switch. Order the correct switch from the manufacturer.

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