MacBook air charger repair

Whether or not your product is in or out of warranty, you can take your adapter to an Apple Authorized Service Provider or Apple Retail Store for evaluation and replacement if necessary. Pending the results of the evaluation, you may or may not be eligible for a replacement adapter free of charge. Signs of accidental damage would negate any coverage. Be sure to bring in the computer used with the adapter; it is required to process potential adapter replacements.

Apple Portables: Troubleshooting MagSafe adapters - Apple Support

it also says:

"The Apple-Authorized Service Provider or Apple Retail Store will provide you with your service options after assessing your adapter."

In my case the service option was always "buy a new charger". I would still go to Apple and ask - perhaps it has changed now. Anyway one could in principle buy a broken charger of the same time, in which the power cord is not damaged, and replace the power cord from the other charger. Will be much cheaper than buying a new charger. But it should be done in accordance to electronic safety standards and performed by someone who deal with such repairs professionally, say any TV repair place.

Aha and beware: there are $5 replacement cords avaiable in the internet. Those seem to circumvent some features of the one-wire protocol with which magsafe connector speaks to the Mac. I would not recommend using them. For example one that I have used does not admit the normally present one second delay between attaching the magsafe and switching on the power. This is dangerous as if you switch the magsafe slowly you may cause sparks and short circuits.

Wrapping it with tape is fine. I have the original charger that came with my Air from 2010. The outer cover near the magsafe split and peeled off many years ago. I have taped and re-taped it several times. I actually bought a second charger and it also had the same issue. It is also taped up and fully functional. The cord has a layer of metal mesh over the wires and neither of mine has ever had any issue with charging. Black electrical tape may not be the best looking choice.

Pete