My MacBook charger stopped working. The fuse went. Is it replaceable

..Valen_98:

"If your power adapter still isn’t working, you can bring it and your Mac notebook

to an Apple Authorized Service Provider or Apple Store for evaluation."

To replace the power adapter is a recommended cure when its internal fusible link

has resolved a potential threat; the unit gets replaced. There's nothing inside to fix.

A reliable source for replacements can be through resellers, such as OWC online.

Various power adapters for MagSafe 1 or 2, are available, often at discount.

• Apple MagSafe Power Adapters from MacSales.com

https://eshop.macsales.com/shop/accessories/apple-magsafe-power-adapters

Some are rated higher than an original spec version your MacBook may have included

with it, when new; any excess output is safely & automatically reduced for your device.

Get the correct MagSafe 1 or 2, ~ and of at least the minimal matching power

output. Your MacBook (air/pro/original, etc) shipped with either version 1 or 2.

For much newer 12-inch MacBook retina (2015+) with non-MagSafe 'USB-C' port,

contact retailer or Apple store; or AASP for a replacement; OWC likely has one.

Fuses are a protection device utilized to prevent damage to the device being charged; something failed bad enough to cause the fuse to blow. Usually they fail on over current since they're rated in amps or milliamps. I'd not trust a cheap old re-fused charger on an expensive MacBook, but it's your call.