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Replace GTX 327 with 335..Have Waas Gns 430w

Tcheairs

Well Known Member
Many posts on this but can't seem to find one which is an identical situation . I have the GTX 327 and would like to replace it with the GTX 335 (without GPS I assume) to achieve ADSB out. I have a GNS 430w (external antenna) which is interfaced with my Dynon FltDek D-180 MFD.

I know I will need a new tray for the longer 335 but are there plug and play wiring harnesses available that make the wiring connections relatively simple?
I don't do schematics very well.

I'd appreciate input from anyone who has been through this swap. Any suggestions of a vendor who would also be helpful with the installation?

Thanks
 
Step 1. Hold down the secret key while you boot up the 430W, to see the hidden menu. Scroll to the RS232-out ports, see if format "ADSB+" is available (must have the "+". If the 'adsb+' format is not shown, then your first step is talk to a Garmin dealer to get the 430W software upgraded. Expect to pay about $100, although if you promise to buy the transponder from him he'll probably do it for free. You can skip this if your 430W is less than 4 (??) years old, or has had its software updated in that time frame.
Step 2. You will need to open up the shell of the connector on the back of the 430W, and insert a new pin with crimped wire into an unused RS232-out location. (Unless you already have a wire pigtail there). Then re-assemble the connector shell. Depending on physical access, this can call for a lot of upside down, body twisting work. Go back into the hidden menu, and configure this port for adsb+ and the baud rate called for in the transponder documentation. Run this wire to the transponder. Hook up everything else the same way your current transponder is wired.
Q: Have you considered the Dynon transponder (basically a slightly modified Trig TT22)? It interfaces well with the Dynon equipment (even more so should you upgrade your EFIS), remote mounts, freeing up panel space, and, best of all, is noticeably less expensive.
 
Obviously the "plug and play" euphemism does not apply here..I had hoped to get this done for less than 5 grand..looks like that won't happen if I wind up at the local avionics shop...guess I'll just put one of those tail light "thingys" or something
 
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