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Single Wire Issue between GTN 650 and PFD

macrafic

Well Known Member
I am finishing up the configuration of my G3X (non-touch) system. I have a single issue that is driving me crazy, and that issue is the failure of the MapMX signals getting to the PFD from the GTN 650.

I have GTN 650 P1001 pin 8 (GPS RS-232 Out 1) wired to PFD P3701 pin 29 (RS-232 IN 3). I have configured my PFD Comm port so that RS-232 3 is set to MapMX. I have configured the GTN 650 RS-232 1 to OFF and MapMX Format 1. The panel was wired by SteinAir, and Chris has verified the wiring and settings here. Yet. in my PFD Comm Port Configuration, the RS-232 3 is red-X'd. Apparently, the mapmx info is not getting from the 650 to the PFD for some reason. Any idea what I should be doing next to troubleshoot this issue?

I have verified continuity for this one wire. Verified that the wire is not accidentally grounded. Also validated that the wire is in the right numbered socket on both ends (PFD and GTN 650)

Chris (SteinAir) mentioned I might try using RS-232 2 (instead of 3) on the PFD. He seemed to vaguely recall some kind issue with the 3rd RS-232 port. So, I will try that tomorrow.

I have sent Garmin support an email regarding this issue and am awaiting their response.

But, VAF is always so responsive, I thought I would give it a shot. I want to close up the front top skin and this is the last wiring problem I have. SO CLOSE!!!!!!

Anybody have a suggestion?
 
Hello Rich,

We don't see your email in the inbox for our G3X product support address (below), but perhaps it just hasn't arrived yet.

It sounds like you have checked the most obvious things. One other subtle detail to note is that the GTN will not output RS-232 data when it is in configuration mode, nor will it output RS-232 data in normal mode until after you have advanced through all the copyright and disclaimer pages. If you have your GTN in config mode, this would explain why you are not seeing any RS-232 data output. Give it a try and see if that helps.

- Matt
 
Rich,

I had a problem with the same connector on my gtn650. While troubleshooting another issue, I found a single pin that the pin couldn't seat properly. The internal ring that holds the pin in place failed. This enabled the pin to be pushed back, causing intermittent issues. I didn't find it when I performed continuity testing. It tested fine. I happened to catch it when adding another wire for a new function.

This may not be your issue, but it is something to check. Yes, it's a pita replacing that connector when the service loop didn't allow easy access. Especially for an old fart with bifocals. :)

Bob
 
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