Anyone have experience trouble shooting a KX155 installation for Nav?? I have a 155 installed in a Maule I bought last year that the nav doesn't seem to be working right. It's connected to a Century HSI with G/S that works fine when switched to GPS. Ok, when I dial in a VOR I hear a nice clear morris code but the HSI does nothing and when I pull the bearing knob it shows "---". I tried a friends 155 and I get the same. I changed the diplexer and I get the same. I've tried 2 different VOR stations in my area with the same results. Any suggestions....
With the decommissioning of VOR stations, I would consider asking your avionics shop to test the system with a ground VOR tester. Only takes 15 minutes to go through all the heading and deflections to verify your set up. With 2 radios doing the same thing, look at the wiring.
What switch are you using? Could be a broken or misconnected wire, or a problem internal to the switch. Download a copy of the KX155 install manual and you'll see it includes sample wiring diagrams for connecting to CDI and HSI. Get something to test continuity and start with that. C.