morning folks just wondered if anyone knew what sort of volt reading I should be getting out of the 3 pin cable that plugs to the back of the alternator... Discovery TD5 1999.... I have another thread where ive posted about alternator issues .... basically I've changed the alternator due to lack of running voltage.... testing from the bolt where the cable fastens onto it and onto the alt casing was still showing 12.4v running so I'm suspecting I've bought a duff recon?? But I'm unsure about the cable that plugs in at the back.... would this affect how the alternator works?....TIA people.

As you've already been told in the other post, the output from a good alternator on the thick brown wire should be in the region of 14-14.5 volts.
The white/green wire should have the battery voltage on it and the brown/yellow wire is the one that operates the ignition light on the dashboard.
You bought a "recon" alternator which in all likelihood is faulty, it happens.
Get it back to the supplier for replacement.
Multiple posts are not going to get multiple answers, I'm sorry.

This is the 3rd thread you've posted on the same issue. Please continue in your wits end thread.

Thread closed to avoid repetition and confusion.