I noticed the DRLs weren't working anymore, so I pulled the 4114K bulbs(similar to 3157 but of higher wattage and longer life) out and put in new ones and the DRLs are working again. However the old bulbs passed the multimeter test for continuity on both filaments and they light up (thick filament) when I apply 12V to it. I likely have arcing corrosion on the socket contacts and perhaps a bit of fretting corrosion. I expect the new bulbs might not stay lit for long before arcing corrosion reappears. If I replace the sockets I will likely expect the same corrosion a few years hence. I am going to replace the 4114k bulbs with led equivalents and not bother replacing the existing sockets. The 1/2 amp draw vs 2.15A draw should go a long way in preventing further arcing damage. Exact same thing happened with my rear brake lights a few years ago. I had no brake lights but the bulbs worked when powered up without the sockets. I replaced the bulbs with leds and have had no further problems since. It seems to me that the miniaturised sockets cannot handle their design currents well. The old 1157 sockets could handle currents better than the later 3157 sockets.