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Hi guys, I have a Mooney M20K with an HSI and KFC150. It always passes the auto check fine on the ground and all. My issue is when I’m flying an ILS approach and want the autopilot to fly it. The localizer bars come online many miles out and the plane turns and tracks down that just fine. At about 10 miles out the glide slope bar on the KI206 (secondary VOR/localizer/GS) indicator pops up showing I’m below the glideslope which is normal but the glideslope flag on the HSI is still showing. After a few more miles and when I’m usually above the glideslope the glideslope bar on the HSI finally decides to wake up. By then it’s too late for it to couple to the autopilot and have the GS light come on and for the autopilot to track the glideslope although it’s still tracking the localizer. Sometimes I’ll use the control wheel steering button to “nose dive” a bit so the plane will descend down through the glide slope and then the GS light on the autopilot will come on and then it will take over and fly the plane down to the runway. It’s like the signal to the Glideslope portion of the HSI is weak or something. Isn’t it the same antenna as the KI206? Then today I flew it and the GS light on the autopilot won’t come on at all whether I fly down through the glideslope or not and the autopilot never does connect and follow the glideslope although the localizer is tracking fine. (The GS light isn’t burned out). When I took it to the avionics shop about 8 years ago they did an “overhaul” on the HSI and “turned up the signal” whatever that means and said they didn’t see any thing wrong with it although they didn’t fly it. They said it could be that some moron painted the fin type antennas on the tail with metallic paint. I removed the paint and it didn’t make much difference plus the KI206 seems to work just fine. Is it possible to swap the wiring from that portion of the HSI with the KI206 and see if it behaves differently? Any ideas? I’d greatly appreciate any help. Thanks. Jay