Pajero 4WD light flashing and I'm nervous about the diagnosis

The 4WD warning light on my Pajero has started flashing intermittently, sometimes staying on for a whole journey and sometimes going off after a few minutes. The car still drives fine in normal mode but I haven't dared engage 4WD since it started. I know these systems have sensors and actuators that can fail, and I don't want someone guessing at it and replacing expensive parts one by one. I'm in Musaffah so I've been looking into Certified Mitsubishi repair in Musaffah , but I want to know what I'm likely dealing with first. Has anyone had a flashing 4WD light on a Pajero and what was the cause? Also, is it safe to keep driving in 2WD while it's flashing or am I risking damage to the transfer case?