ALT-2 Auto Repairs how to Test a Fuse
What can be done once the power in a car is turned on but the stereo suddenly doesn’t power up? How about an internal light or other electrical system component failing to turn on? It is possible that an auto could have complicated electrical system fault but most of the time this is not the case; it is simply a fuse.
♦ What is a fuse?
A fuse is an intentional fault in an electrical system. The reason for a fuse is in the case of a short or electrical surge to have the fuse break rather than cause real damage to the electrical components. Every electrical system will have a fuse in line with it prevent damage and make repair of the electrical system simple and inexpensive
♦ How to test a fuse: Visual.
Without having access to tools someone can get a fair indication of the condition of a fuse with a visual inspection. It will not ALWAYS show a bad fuse, but often the indications will be clear and indicate if it is even worth getting a tool to check further.
To check fuses visually look at the clear side of the fuse. There will be a thin strip of metal from one end to the other end without any apparent breakages. If a breakage of any sort is seen, the fuse is bad. If a breakage is not seen there will be a need check the fuse electrically to have 100% assurance the fuse is good, but the fuse passes the initial inspection.
♦ How to test an automobile fuse with a test light.
The easiest method of testing a fuse electrically is using a 12 volt test light. These are very inexpensive tools that can be purchased in any automotive or hardware store. It consists of a clipped lead and a probe with a light. Using this tool is simple. Turn the car ignition key to the “on” position. There should be a pair of little metal tabs on the top portion or every fuse. The first thing to do is put the clip to a good “ground” in the car. Next connect the fuse tester to the each of the metal tabs. If neither tab lights the light there is a problem with the ground connection somewhere, try to reconnect the ground clip to another place with bare metal until at least one of the tabs makes the tester light up. If both of the tabs on top of the fuse light when the tester is connected to them, the fuse is good. If only one tab lights the test light, then the fuse is bad.
It is pretty simple, just remember that part. One tab lights tester: bad fuse. Both tabs light tester: good fuse.
If there is any doubt about whether a specific fuse is good or bad, simply assume it is bad. Fuses are cheap. If fuses keep blowing as they are replaced, there is likely a more serious issue with the electrical system and a professional should be brought in to check out the situation.
