Unlike a circuit breaker, all fusible links can't be reset and need to be replaced once it is blown. Take the following guidelines to replace it by yourself. 

Materials to prepare:

• New and Proper Size Fusible Links
• Wire Cutter
• Wire Stripper
• Heat-shrink tubes
• Solder
• Soldering Gun
• Heat Gun
• Wire Crimps

1. Dismount the negative pole of the battery
2. Cut off both ends of the blown fusible links from the main wire harness
3. Strips the ends of the new fusible link for 1-2 inches
4. Blend the stands of copper of one end of fusible links with the main wire
5. Puts crimps onto the connecting point and solder it to build a stronger connection
6. Slide the heat shrink tube to cover the joint area
7. Use the heat gun to fasten the heat shrink tube
8. Repeat 4-7 for the other end of the fusible links

(Originally posted on Easybom)