What to do, what to do... I have a 172S with a KLN 94/KMD 550 combination. The KMD 550 complains during self-test that one of the panel LEDs doesn't work. It's a spurious error: all the LEDs work perfectly. Every other aspect of the device works great. It's flown this way for years now, without a single complaint from any mechanic looking at the aircraft or this issue. Everyone has signed it off as airworthy. Until now. The GM for the club it's on leaseback with wants it placarded in-op due to this. Everyone else has read the indication as spurious and that the device is actually working perfectly. This GM wants a stricter reading where this indication requires the thing pulled. Fixing the issue directly is about $5K. That would be a silly amount of money to spend on this ancient tech. Better to save it for a later GTN install. But am I really stuck with making that later now?