bobcat charging system help!!!

a friend of mine has a mini exavater with a little 4cyl kubota. it quit running and they replaced the alternator but it still wont charge. there was a small red wire they took off the alternator that the guys at bobcat said they didnt need. anyone know why it wouldnt charge. could that red wire be some kind of voltage regulator thing? any ideas would be nice.
thanks

whats the model number? i maybe be able to help. im in good with the local dealer around here.

im not positive. its a mini excavator. i thnk it was a 330 model. i looked at a code ontop of the engine and v2200 comes to mind but thats just maybe. the 330 model seems right tho, its somthin like that. srry i aint got the specifics.

ill get back to you in the AM.

ok. that would b great. thanks for the help!