*Repairs: Small vehicle repairs. Tracklinks, Gundamage, extinguish fires..
I suggest the crew exits, and 'use a repairbutton' while facing the damage perhaps for a number of seconds/minutes? Not to fast, but cant be 10+ minutes, lest the round'll be over or it would be in some cases faster to get a new tank. But around 1 minute app? maybe more/damage?
This would not repair the tank(colours), nor the engine(Large damage, meant for technicians), but small things: Fix a shattered track, repair a jammed gun or MG, Extinguish the fire, so that huge smokecolumn stops and doesnt betray your position to each enemy in the surroundings,...
This would expose the crew, but its that or ignore the damage. However on some occasions, you cannot ignore it.