Battery load failure

Good to everyone.

I am new in the forum and I have a colstand for those who can advise me.

I have a Seat Cordoba 1.9 SDI of 2005 with the following problem:
the alternator takes 11.7 volts towards the battery but after changing the alternator it gives me the same output voltage.
I have begun to look and in the two cable connector that arrives at the alternator does not arrive or leave tension. And on the other hand the battery light of the painting does not turn on to me.
My questions are:
Should tension arrive in any of the cables to excite the alternator?
Could you tell me what it is?
The switchboard regulates something in the alternator?
On the theme of the light of the painting:
one of the cables that leaves the alternator is that it feeds it?

Hello, the dashboard checks that it is not burned because this light closes the load circuit, the alternator comes a positive pulse that comes from the pilot light and success the alternator to load, also check the alternator fuse, now when the light does not go out, check the coals, and when the irregular load is checked.

Thanks Jotaele.

I will prove this to have such.

By the way, don't you have the electrical scheme?
If so, it would hurt me very well.

I will tell you.
Sincerely, Raúl.

Well tell you that in the end I have found two loose cables ...
and indeed they were the two cables that go to the alternator (the excitation and the control of the batteria light of the painting).

Inform you in case you find the same anomaly as mine, it could be the connector under the starter engine. The colors of the cables are brown and red the number 2 (of the connector) and blue the number 1 (of the connector).
After the connector the blue is still blue and the brown and red is combined in lilac. These are the ones that have broken.

I hope this explanation serves someone with someone.

Thank you so much.