i have a diode tester on my multimeter so i know mine it good. then i tested it on an ohms scale and it does show resistance. so if you have an ohm meter you can get an idea if it good or not. you need to make sure you have you leads on it right because you will only measure resistance one way. black lead (<--) red lead. there will be a pic on the diode like the one i just typed. that arrow is the flow direction of the diode. it should be pointing at the top of the fuse box while pluged in. i measured it on my 600 scale and it showed 308K ohms
