Sceniro...............1961 Cessna Skylane with generator. Just installed a Garmin 430. also has a KX 155 nav/com, push to talk on left and right yoke. Prior to installation no problems, by the way the 430 replaced a KX 175. Here's the problem. When using the 430 and you push to talk using the switches on either yoke, the generator light comes on and the amp meter shows a big draw, (needle moves to the left) this occur at all RPM ranges including cruise power. One other thing, the problem seems to exist when using certain comm frequencies. Everything is fine when using the KX 155. It's at a different radio shop now then did the installation. This is what the new shop has done so far. Replaced comm antennas and coax. Replaced all wiring going to the 430, checked all pins, checked all grounds, checked antenna coax plug in 430 tray, bypassed amp meter, they've also called Garmin, the 430 prior to installation had been sent to Garmin and completely gone through with a new warranty. Tried a different 430 with same results. Anyone have any ideas?