When a single electrical item stops working, like a radio, a socket or one set of lights, a blown fuse is often the simple cause. Checking and replacing one is a five minute job.
Find the right fuse
Cars have one or two fuse boxes, usually under the dash and under the hood. The lid or the manual has a diagram showing which fuse protects which circuit. Find the one that matches the item that stopped working.
Test the fuse
Pull the fuse with the little puller in the box or with needle nose pliers. Look through the clear plastic top: a blown fuse has a broken metal strip inside. For certainty, a cheap circuit tester or multimeter confirms whether current passes through.
Replace it correctly
Fit a new fuse of the exact same amp rating, shown by the number and colour on top. Never fit a higher rated fuse to stop it blowing again, because the fuse is protecting the wiring from overheating. If a new fuse blows immediately, there is a fault to find.
Frequently asked questions
Can I use a higher amp fuse?
No. A higher rating can let too much current flow and overheat the wiring, which is a fire risk. Always match the rating.
Why does my fuse keep blowing?
A repeated blow means a short or an overloaded circuit. The fuse is doing its job, so trace the fault rather than upsizing it.
Keep a fuse kit and tester handy. See our car accessory guides.
