Circuit Protection - Fuses
Special Tools
EL - 39200B Digital Multimeter (DMM)
For equivalent regional tools, refer to Special Tools .
- Good fuse
- Bad fuse
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is an excessive amount of current flowing through a circuit the fusible element will melt and create an open or incomplete circuit. Fuses are a one time protection device and must be replaced each time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and examine if the element in the fuse is broken (2). If not broken (1), also check for continuity using a Digital Multimeter (DMM) or a continuity tester. If the element is broken or continuity is suspect, replace the fuse with one of equal current rating.
Fuse Types
| Current Rating Amperes | Color |
|---|---|
| Mini | |
| 2 | Gray |
| 3 | Violet |
| 5 | Tan |
| 7.5 | Brown |
| 10 | Red |
| 15 | Blue |
| 20 | Yellow |
| 25 | Natural |
| 30 | Green |
| Low Profile Mini | |
| 2 | Gray |
| 3 | Violet |
| 4 | Pink |
| 5 | Tan |
| 7.5 | Brown |
| 10 | Red |
| 15 | Blue |
| 20 | Yellow |
| 25 | Natural |
| 30 | Green |
| Micro 2 | |
| 5 | Tan |
| 7.5 | Brown |
| 10 | Red |
| 15 | Blue |
| 20 | Yellow |
| 25 | Natural/White |
| 30 | Green |
| Micro 3 | |
| 5 | Tan |
| 7.5 | Brown |
| 10 | Red |
| 15 | Blue |
| Maxi | |
| 20 | Yellow |
| 25 | Gray |
| 30 | Green |
| 40 | Amber |
| 50 | Red |
| 60 | Blue |
| J-Case | |
| 20 | Light Blue |
| 25 | Natural |
| 30 | Pink |
| 40 | Green |
| 50 | Red |
| 60 | Yellow |
| Low Profile J-Case | |
| 20 | Light Blue |
| 25 | Natural |
| 30 | Pink |
| 40 | Green |
| 50 | Red |
| 60 | Yellow |
| M-Case Unslotted | |
| 20 | Light Blue |
| 25 | Natural |
| 30 | Pink |
| 40 | Green |
| 50 | Red |
| 60 | Yellow |
| M-Case Slotted | |
| 20 | Light Blue |
| 25 | Natural |
| 30 | Pink |
| 40 | Green |
| 50 | Red |
| 60 | Yellow |
| Midi | |
| 30 | Black |
| 40 | Black |
| 50 | Black |
| 60 | Black |
| 70 | Black |
| 80 | Black |
| 100 | Black |
| 125 | Black |
| 150 | Black |
| 175 | Black |
| 200 | Black |
| Mega | |
| 40 | Black |
| 60 | Black |
| 80 | Black |
| 100 | Black |
| 125 | Black |
| 150 | Black |
| 175 | Black |
| 200 | Black |
| 225 | Black |
| 250 | Black |
| 300 | Black |
| 350 | Black |
| 400 | Black |
| 450 | Black |
| 500 | Black |
| Single Z-Case | |
| 125 | Black |
| 150 | Black |
| 175 | Black |
| 200 | Black |
| 225 | Black |
| 250 | Black |
| 300 | Black |
| 350 | Black |
| 400 | Black |
| 500 | Black |
| 600 | Black |