Where do I start checking for electric problems?
When one of your electrical systems starts to malfunction, the first and easiest part you want to check is the fuse box
. Usually, a blown fuse
just causes a minor car electrical problem, like back up lights
or interior lights not working, not being able to use your radio, or some of your climate control features not functioning properly. In rare cases, though, a blown fuse can mean that your car won’t start. How to replace a blown fuse?
Located on the underside of the cover or in your owner’s manual, there is a diagram of which fuse connects where. Find the fuse corresponding to the component you are having problems with and inspect it. If the glass or plastic appears dark or burnt the fuse is probably blown and should be replaced. Fuses can also blow if someone has replaced a bad fuse with one of improper amperage. Always make sure to replace each fuse with a fuse of the same amperage, and make sure that the proper fuse was being used to begin with, to avoid a bigger problem. What’s next after checking the fuses?
Next thing to check after the fuses is the wiring. Every electrical circuit needs to create a way for electricity to get to the device you are powering and for the electricity to continue back to the battery. If one of the wires delivering power or return power is not making a good connection, your electrical component will not work. Why does a wire fail?
Bad connections can happen for a variety of reasons. As wires carry electricity they get hot, so it is possible, after a lot of use, for a connection to melt and no longer make contact. If the connector is outside of the cabin of the car it could become rusted or dirty to the point where electricity will no longer flow. It is also possible that from use and vibrations the wires simply disconnect. In this case, you need a wiring diagram for your vehicle, a circuit tester and a lot of patience. How to check a light bulb or its socket?
The next thing to check is the component itself. To name a few examples, if a light in or on the car isn’t working, check the bulb
. Take it out and give it a few small shakes, if you hear rattling inside, or the glass is blackened, the light bulb
is no good. If your fuses, wiring, and bulb are all intact, it may be the lamp socket
. To test a socket, insure that there is no heavy corrosion, if corrosion is found, simply clean off with a wire brush. If the socket looks intact, (with the light in question switched off) test the contacts in the socket with a 12-volt auto test light, if two out of three light up but the bulb still doesn’t work when plugged into it, the socket is bad.