there are several ways you can use meter to see if you get a reading from side to side or turn on the ignition switch to on motor not running take a test ligt and touch the top of the prongs if the light, lights up on both sides the fuse is good . if you pull the fuse out you can look throught it to see if the element is in tack if it looks broken it is bad.
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i was replacing a fuse one day it looked good scratched my head and looked at it. turned out the inside fillament where it makes contact on the ends under the silver cap was broke i had it in my hand for 2 or 3 hours, never gave it a second thought, i was looking at it real close and hell just decided to twist it for some ironic reason ( it came apart) the fuse looked new felt new looked good. until it came apart. put a new one in problem solved. the ole saying is: ( nothing is ever what it seems).
Fuel pressure test. Of course if it is not running, fuse and relay are good then it is bad.
Take a look at the fuse. When you hold it up you should see, on a good fuse, a small wire running from one side to the other. If you see the wire and it goes from one side to the other without a break then it is a good fuse. You can tell when they are bad because the wire will be broken and melted.
Fuse are clear plastic so it can be check visually. If the wire in the fuse isn't broken/burnt it is good. Better yet you can use a multi-meter or test light to check the fuse and for power without removing the fuse. If you have power on both sides of the fuse the fuse is good.
if the bulbs are not bad, it is the fuse, if the fuse is good, its the wiring.
Bad horn? Bad relay? Bad horn switch?
They could be smiling if it is good news or if they are frowning its bad news.
you check the middle of it and if it is black or the little wire is broken it is bad or just use a fuse checker and if the light doesn't turn on it is bad Call the parts guy at your nearest dealer
The fuel pump will not come on. Of course this could be a blown fuse or the pump itself has failed. Check the fuse and if it is good then install a new relay to see if that solves the problem. If not the pump is bad.
prob a bad fuse or switch.
Look at it closely to see if it is blown. If you cannot tell by looking then check it with an ohm meter.
very unreliably it can only tell if it is good but not how good and will tell you if bad but not how bad. it is only good for pass no pass testing.
if they are bad then they will do stuff to hurt you. but if they are good then they will do stuff to help you