What happens when my charger turns yellow?

it is showing that its charging. look to the battery indicator if that has a bolt on top of the battery it is charging wait for it to charge fully than it must turn to green when it is green it means it is fully charged.

If its both green and amber according to macrumors page that user SandsOfArrakis posted it is charging at a lower voltage and you should go to a genius to replace it

Does the battery charge with the yellow color? And if so, does it turn green when the battery is fully charged?

I've found this site while googling around.

https://forums.macrumors.com/threads/magsafe-has-yellow-led-while-charging.562048/

Suggests the charger might be faulty.