Test fuses in a recreational vehicle by using a test light, a voltmeter or a multimeter set to either ohms or volts. Different equipment and settings are used depending upon whether the fuse is being removed from the circuit or being tested with live current.
The first step in testing a blown fuse in an RV is gently removing the fuse with a plastic clamp called a fuse puller. Using a fuse puller allows for safe visual inspection and further testing without risk of shock.
Once the fuse is pulled from the circuit, it can be attached to a multimeter set to ohms. This setting tests the amount of electrical resistance provided by a fuse. A result of 0 is ideal. If the fuse can't be read by the multimeter, the fuse is broken.
If the fuse cannot be removed safely, testing with live current can be done with a test light, a voltmeter or a multimeter set to volts. Always ground the tool first to prevent shock. Probe the exposed metal ends of the fuse with the tool's test leads. If the fuse is in working order, the test results should show a small amount of voltage.