you can do the non smart way test it like I did(not recommended but I didnt really care) start car, pull the positive cable and see if the car stays on.
On new cars doing this will turn off the car as there are failsafes, but not in the e46.
take it to an alternator shop/ independent
"The hardest thing is to forgive, but God does. Even if you murdered or robbed, yeah it's wrong, but God loves.
Take one step toward him, he takes two towards you. Even when all else fails, God support you.."
Cypress Hill x Rusko - Lez Go (Monista Remix)