That's the polyfuse. Disconnect power, and you should read close to 0 ohms across it. With power applied, you should read around +5v.
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That's the polyfuse. Disconnect power, and you should read close to 0 ohms across it. With power applied, you should read around +5v from either end to ground. reading an open during the ohm test tells you it needs time to reset. Same thing with reading +5 from only one side. Fuse check passes if you get close to 0 ohms and read +5 on both sides when powered up.