I know nothing about cars....
How do you know that you need to change it?
An alternator will often stop working if the Battery Light on the dashboard has failed - it's much cheaper and far easier to change a blown bulb than the alternator.
You disconnect the wires - undo the bolts - remove the alternator - put in the new one and tighten up the drive belt - I would think.
A Haynes Manual or a garage may be useful.
Wikipedia says this...
if the warning light fails or the "exciter" wire is disconnected, no excitation current reaches the alternator field windings and so the alternator, due to low residual magnetism in the rotor will not generate any power. The driver may check for a faulty exciter-circuit by ensuring that the warning light is glowing with the engine stopped.
Good luck...
Peccavi
February 2010
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