those perko ones? i had nothing but trouble with mine. ended up buying a flashlight type one that clamps to the bow as a backup. when you say "inside the fixture" do you mean right before the bulb? you can take the point of the probe and poke it through the insulation just below the bulb . it could be the contact in the hull, or the bulb socket. check for corrosion, clean and apply dielectric grease. good luck



willy
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"I know a taxidermy man back home. He gonna have a heart attack when he see what I brung him." -Quint