GNS430W no comm transmit problem...no audio & "tx"

maduro

maduro

Pre-takeoff checklist
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Maduro
I have a GNS530W and GNS430W.....suddenly, I can not transmit on the 430. It can only receive. When I push the PTT button on the the 430, no audio transmits and I don't see the "tx" on the 430. If I switch over to the 530, I can transmit fine when I push the PTT button. I had flown the plane a week prior and I was able to transmit on the 430. I crawled under the dash and checked the comm cable to see if it got loose but found no issues. I also pulled the 430 out of the tray and checked for bent pins. If the problem is the 430, is there a transmit board that can be replaced? The base price to get the 430 serviced is now $1979. Would like to resolve the problem with a less expensive solution if there is one. Thanx guys.
 
That may be an audio panel problem. What audio panel do you have? To test the 430, find someone else with a 430W, 430 or IFD440 and slide it in and see if the problem persists. If it fixes the issue, your 430 is the problem. If it persists, then a wire or the audio panel is the problem.
 
Yea tomorrow I am going to swap mine out with a 430 that belongs to a friend. If the problem moves to his plane then the 430 is the problem. Will update tomorrow.

I didn't think about the audio panel.... it's a GMA-340. I am hoping it's the audio panel. It's much cheaper to replace.
 
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Check to see if the transmit side of the 430 is on its own breaker. Everything else will work fine if it's pulled. Ask me how I know...
 
Any other GMA340 or PMA8000 or PMA450 will slide into the 340 tray.
 
Does the same problem happen with the co pilot jacks?
 
WDD said:
Does the same problem happen with the co pilot jacks?
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Yea... if I plugin my headset into the copilot jacks, the same thing happens from that seat too. I am headed to the hangar soon to do the 430 swap test.

If it's the audio panel... I'm gonna buy the PMA450B. Not much more than the GMA345...and I've heard PMA's customer service and support is excellent. It's a slide in upgrade but I still have to have an A&P signoff in my logbook.
 
It is the audio panel. It is going bad. The 430 has no issues. I put my 430 into my friends airplane and the comms transmit and received. I put his 430 into my airplane and no transmit. I have ordered a PMA450B at Aircraft Spruce.
 
Curious - what will you do with the old GNS?
 
WDD said:
Curious - what will you do with the old GNS?
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Do you mean what i will do with the old GMA340? I probably will post it on ebay for parts. Garmin doesn't service them anymore or sell parts. There are tons of them out there in the wild. If you are interested in it. Send me an offer.
 
maduro said:
Do you mean what i will do with the old GMA340? I probably will post it on ebay for parts. Garmin doesn't service them anymore or sell parts. There are tons of them out there in the wild. If you are interested in it. Send me an offer.
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My bad. I mis read the PMA 450B for the audio panel with the built in com (PAR200B) which meant you were deleting your GNS. Never mind / carry on......
 
maduro said:
It is the audio panel. It is going bad. The 430 has no issues. I put my 430 into my friends airplane and the comms transmit and received. I put his 430 into my airplane and no transmit. I have ordered a PMA450B at Aircraft Spruce.
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While it certainly can be the 340 going bad, did you happen to check continuity between the 340 P1 pin 12 (assuming 430 is COM 2) and 430 P4002 Pin 4 (as well as ensuring there is power on P4002 pins 11 & 12) to ensure it's not some sort of wiring issue? Upgrading to a 450B is certainly a nice option, and will hopefully resolve it, but just curious if the wiring was checked at all.
 
On a slightly different but almost related topic of replacing things.

At what point do you replace the GNS units? Or do you reckon that you’ll never need to?
 
Ryan: I didn't check the continuity of the wires/pins. I have the GMA340 at home. Is there a way to check the continuity out of the plane? I tried to get a local avionics shop to do a thorough health check but they were two weeks out and the tech said that Garmin no longer services the GMA340 nor offers parts. I think that was his way of tell me to go away.

WDD: My plan at the moment is to replace the GNS units is to upgrade to the Avidyne 4XX and 5XX when the time arrives. Another option for me is to upgrade my plane to Cirrus or Malibu(I have an Arrow).
 
maduro said:
Another option for me is to upgrade my plane to Cirrus or Malibu(I have an Arrow).
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“My home AC unit broke. I’ll fix that by buying a new house.”

I like your style - go big or go home!
 
WDD said:
“My home AC unit broke. I’ll fix that by buying a new house.”

I like your style - go big or go home!
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LOL.... but that's my long term plan to buy the new house due to the broken AC. I hope the 430 & 530 will last me at least another 5 years.
 
Continuity/power checks could only be done in the plane (testing to make sure the wiring is intact on the mic key line between the 340 and 430 and the power input to the 430). As @GeorgeC alluded to the 430 COM section has separate power input... but the receiver will still function without the COM section being powered. Also, on early 430's the COM section was 28V only, and required an up converter in 14V aircraft, but will still receive just fine without it functioning as the receiver is powered through the GPS power input.
 
Are there independent wires run from the mic to the 430 and 530? The comm on the 530 worked for transmit/receive. If the audio panel does the internal switching for the 530 and 430 comms wouldn't that indicate the mic wires are ok?
 
maduro said:
Are there independent wires run from the mic to the 430 and 530? The comm on the 530 worked for transmit/receive. If the audio panel does the internal switching for the 530 and 430 comms wouldn't that indicate the mic wires are ok?
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There are independent wires run from the audio panel to the 430 and 530 (com audio hi/lo, mic audio, mic key, and nav audio hi/lo). The fact that the transmit works for the 530 indicates that the wiring is intact between the jacks+PTT switch and the audio panel, and the audio panel and the 530, but not that the wiring is intact between the 430 and the audio panel.
 
maduro said:
Ryan: I didn't check the continuity of the wires/pins. I have the GMA340 at home. Is there a way to check the continuity out of the plane? I tried to get a local avionics shop to do a thorough health check but they were two weeks out and the tech said that Garmin no longer services the GMA340 nor offers parts. I think that was his way of tell me to go away.

WDD: My plan at the moment is to replace the GNS units is to upgrade to the Avidyne 4XX and 5XX when the time arrives. Another option for me is to upgrade my plane to Cirrus or Malibu(I have an Arrow).
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That was my plan, too. If you have a Garmin AP, note that Big Gee has not listed Avidyne as a compatible navigator to hook to the AP. I've been 'round and 'round about this, yes, it's the G5's driving the AP and you could actually turn the navigator off and things would work just fine, but Avidyne sent me a cryptic message confirming that Big Gee had not tested their APs with brand A. No one said it was forbidden, but no one said it was okay, either. I will probably upgrade to A when the time comes, and hope that no one notices.
 
I have the GFC500 and have heard that the Avidyne 4XX and 5XX works with it but G man and company A will not officially say they work together. It's cause one wants the other one to pay up!
 
Ryan Klems said:
There are independent wires run from the audio panel to the 430 and 530 (com audio hi/lo, mic audio, mic key, and nav audio hi/lo). The fact that the transmit works for the 530 indicates that the wiring is intact between the jacks+PTT switch and the audio panel, and the audio panel and the 530, but not that the wiring is intact between the 430 and the audio panel.
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I am getting the PMA540B on Friday. I'll slide it in and will report back.
 
maduro said:
The new audio panel PMA540B installed, no more comm issues with the GNS430W.
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Is that the successor to the PMA450B?

(Yeah, probably a typo. But with Oshkosh only 1 week from now, you never know :) )
 
Ooops yea... I meant PMA450B. I am starting to play with all it's features and it's very nice.
 
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