fan side of things will be a faulty sensor, as the ecu might not be getting a proper reading, even though you gauge sensor is working,
As for rear drums, you wouldn't need to mess about with rear bearings, as that will just come off with the hub I would have thought, when you remove the drum, but you might just need to adjust them, as they do need adjustments now and again.
My dad has said, get the arse end jacked up and get a mate to put his foot on the brake, while he has his foot on the brake, see if you can turn the rear wheel. If you can, then adjust it, and do the same on the other side. If that fails, then you will need to put new shoes in.
As for rear drums, you wouldn't need to mess about with rear bearings, as that will just come off with the hub I would have thought, when you remove the drum, but you might just need to adjust them, as they do need adjustments now and again.
My dad has said, get the arse end jacked up and get a mate to put his foot on the brake, while he has his foot on the brake, see if you can turn the rear wheel. If you can, then adjust it, and do the same on the other side. If that fails, then you will need to put new shoes in.