On today’s vehicles there are a lot of electrical components. Each one has a job to do. We will talk about a few of them.
The charging and starting systems are the hard workers of your vehicle. The battery is used to start your engine. With the use of the battery cables, current is sent to the starter from the positive side of the battery and is returned to the battery through the negative battery cable. These cables are heavy cables which will carry a lot of amps. The starter uses the most current of any component on your vehicle. The negative system, or what we call the ground current, uses a heavy cable from your battery to the engine block and smaller cables to ground the body and frame of your vehicle. Now the charging system is used to replenish the current the starter and electrical system uses. The wire from the alternator to the battery is heavy, but not as heavy as the starting system uses.
How do we know if the charging system is working? Your vehicle will have a charge or battery light or a meter. If we think it is not charging, DO NOT disconnect the battery to test — bad things will happen. Systems can tell us things like dim light at night. No starts have to be jumped off. When this happens, have the system checked. With meters we can tell what the problem is. More on other systems later.