12V Fuse Keeps Blowing? Step-by-Step Troubleshooter
Never just fit a bigger fuse. Find out why it blows.
A fuse protects the cable. Don't fit a bigger fuse to stop it blowing. That just moves the failure to the cable. Work through one question at a time. You can go back or start over whenever you like.
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Safety: this troubleshooter is general information. Follow the maker's manuals. Work on 240V AC wiring, including inverter outputs and mains inlets, must be done by a licensed electrician. Have an auto electrician check high-current DC work if you're unsure.
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Read guide →What Size Fuse Do I Need? 12V Fuse Calculator
Free calculator: work out a starting fuse size for a 12V or 24V circuit from its load, and check it against your cable's current rating.
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