Some Useful Information on Fuses used in Vehicles

Fuses or fusible links are provided in vehicles to avoid fire hazard in event of short circuiting in electrical system of your vehicle.Here are some useful tips on fuses or fusible links in vehicle:

1. You can check for a burnt fusible link with help of a multimeter or using a custom-build continuity tester.Alternatively a fuse can also be checked for it health by careful visual inspection.
2. If a fusible link burns out, there is a short or some other problem in the circuit. Carefully determine the cause and correct it before replacing the fusible link.
3. The fusible link will burn out within 15 seconds if a higher than specified current flows through the circuit.
4. When a fuse is blown, there are two probable causes. The two causes can easily be determined by a visual check after removing the fuses.The two probable causes are : 
• Fuse blown due to over-current. : Prior to replacing the fuse with a new one, check the circuit for a short and the related parts for abnormal conditions. Only after the correction of a short or replacement of abnormal parts, should a fuse with the same ampere rating be installed.
  
• Fuse blown due to repeated on-off current : Normally, this type of problem occurs after a fairly long period of use, and is less frequent than the above. In this case, you may simply replace with a new fuse of the same capacity.
  
5. Always use fuses of recommended ratings.Never use a fuse of higher rating than the recommended rating.Also never use a wire in place of a fusible link this could lead to fire hazard in event of short-circuiting.However,in case of unavailability of fuse of recommended rating you can use fuse of lower rating than the recommended rating but use of wire in place of fuse or fuse or higher rating than recommended rating is strongly not recommended.
   
   
6. The circuit tester for testing fusible links,relays and dc voltage output of electrical devices installed on your vehicle is shown below:
   
   This tester can be built from electrical tester used for testing Live Wire of Electrical Mains by replacing the bulb of the normal electrical tester with small 12Volt bulb used in vehicles.