Wood Termite Damage
Termite damage is usually not that hard to spot
and you'll be looking for holes in the wood, missing sections of wood
and what looks to be like paint flaking off of the wood.
As you can see in the picture above the paint looks like it is flaking off of the wood and could give you the illusion that there is only paint damage.
To check for further damage you can always use a awl and try to press it into the wood looking for soft spots.
Usually if you have some termite damage you have more termite damage so examine the building more closely.
Exterior termite damage like this is usually easy to find because you can visually see it, the only problem is most of the time you can't see all of the termite damage throughout the home.
I would recommend replacing instead repairing with wood filler this damage because it looks pretty bad.