I removed the battery from my 1998 diesel van to check the alternator
connections.

There are three leads from the positive terminal:

1. Red cable goes to a connector block on the adjoining wing,
2. Sleeved cable goes through the rear of the battery tray towards the
alternator (I presume that it must go to the starter motor)
3. A second thick red cable has a small connecting block attached and
goes ....... nowhere. It almost touches the rear of the battery tray
which would not be very safe.

What, if anything, should be attached to this third cable.

I will have a look underneath the vehicle tomorrow for any loose
connections but would be grateful for any help.