How to Change the Alternator on a 2001 BMW 330ci

Removing the Old Alternator
1. Verify that you have the radio code for your BMW 330CI so that you can operate the radio after replacing the alternator. You will need to manually enter this code in your radio after reconnecting the battery. You can find this code in your owner's manual or your new vehicle paperwork.
2. Turn the ignition to the “Off” position.
3. Disconnect the negative (black) battery cable using a wrench.
4. Remove the air cleaner assembly using a ratchet, ratchet extension, socket and a Phillips head screwdriver if necessary. The air cleaner assembly sits on top of the engine and is connected to the throttle body on the intake manifold.
5. Unplug the wiring harness from the back of the alternator. The alternator is in the upper area of the engine compartment, next to the engine and is driven by a belt connected to the crankshaft pulley.
6. Remove the battery wire retaining nut from the back of the alternator using a wrench. If your alternator has a ground wire connected to it, detach the retaining nut as well to disconnect the wire using a wrench.
7. Loosen the hose clamp from the cooling duct connected to the alternator using a Phillips head screwdriver and detach the hose from the alternator.
8. Hold the adjusting nut of the lock bolt onto the rear of the alternator with a wrench and loosen the lock bolt with a ratchet and socket.
9. Loosen the alternator belt tensioning bolt in front of the alternator using a ratchet and socket, then slip the belt off the alternator pulley.
10. Unfasten the alternator mounting bolts using the ratchet and socket and remove the alternator from the vehicle.
Installing the New Alternator
11. Position the new alternator into place in the engine compartment and start the mounting bolts by hand. Then tighten the mounting bolts using the ratchet and socket.
12. Slip the alternator belt over the alternator pulley and torque the tensioning bolt to 60 inch-pounds using a torque wrench.
13. Hold the lock bolt adjusting nut with a wrench and tighten the lock bolt using the ratchet and socket.
14. Reinstall the cooling duct hose onto the alternator and tighten the hose clamp using the Phillips head screwdriver.
15. Reattach the battery wire and ground wire, if equipped, to the rear of the alternator using the wrench.
16. Reconnect the wiring harness to the rear of the alternator.
17. Reinstall the air cleaner assembly using the ratchet, ratchet extension and socket and the Phillips head screwdriver, if necessary.
18. Reconnect the negative (black) battery cable.
19. Reenter the radio code using the radio control buttons.