As I was preparing to head down to KSLE for the Garmin open house this afternoon, I noticed several issues relating to my GNS430 (the irony!) that caused me to cancel my trip. I just flew my airplane the other day, and fly it regularly. For reference, I have a GRT Sport EFIS, GNS430, GTX327 transponder, PS Engineering intercomm, and two MGL backup instruments.
First, roughly 30 seconds after turning the radio master switch on, a high-pitch tone would start increasing in volume, and persisted to the point where it was difficult to hear ATC over the radio, and my passenger over intercom. So, I went in to troubleshooting mode for this issue and found:
I washed the airplane for the first time 24 hours prior, so I'm wondering if I maybe got something wet in the panel, or possibly did something to an antennae when I was cleaning? Or perhaps the timing of the washing and cleaning is coincidental?
Any thoughts or ideas out there on either the tone or the 430 messages? Thank you!
First, roughly 30 seconds after turning the radio master switch on, a high-pitch tone would start increasing in volume, and persisted to the point where it was difficult to hear ATC over the radio, and my passenger over intercom. So, I went in to troubleshooting mode for this issue and found:
1) ATC could not hear the tone over the radio; comms over frequency were clear;
2) When first turning the radio master on, I could hear ATC clearly over the radio, and could clearly hear over the intercom with the tone not present at first;
3) It made no difference if the engine was on or off...the tone would still always return;
4) The tone seemed to start at around the time both the 430 and the MGL instruments are finishing booting up, though I haven't been able to definitely isolate it to either the 430 or one of the MGL instruments;
5) The headsets both seemed to be seated properly, and the headset jacks didn't seem loose. I heard no difference in the tone with messing with the headphone jacks, and the tone did not change when unplugging one headset or swapping headsets/jacks. The issue does not appear to be related to the intercom;
6) I don't have circuit breakers that can be pulled for some components like the MGL instruments, but I cycled power one at a time to the systems that I could and found no change in the tone. I was not able to cycle power to the 430 or the MGL instruments;
7) I crawled under the panel and looked for anything loose at the back of the 430 and found one wire lose. I tightened it but it made no impact on the tone;
8) Changing frequencies didn't change the tone at all;
9) Change in engine RPM didn't seem to change the tone. However, at times the tone would fade slightly and then get louder, but I couldn't correlate that to anything.
I also had the following two messages on the 430 that I'd never seen before: "G/S Needs Service", and "VLOC Needs Service". 2) When first turning the radio master on, I could hear ATC clearly over the radio, and could clearly hear over the intercom with the tone not present at first;
3) It made no difference if the engine was on or off...the tone would still always return;
4) The tone seemed to start at around the time both the 430 and the MGL instruments are finishing booting up, though I haven't been able to definitely isolate it to either the 430 or one of the MGL instruments;
5) The headsets both seemed to be seated properly, and the headset jacks didn't seem loose. I heard no difference in the tone with messing with the headphone jacks, and the tone did not change when unplugging one headset or swapping headsets/jacks. The issue does not appear to be related to the intercom;
6) I don't have circuit breakers that can be pulled for some components like the MGL instruments, but I cycled power one at a time to the systems that I could and found no change in the tone. I was not able to cycle power to the 430 or the MGL instruments;
7) I crawled under the panel and looked for anything loose at the back of the 430 and found one wire lose. I tightened it but it made no impact on the tone;
8) Changing frequencies didn't change the tone at all;
9) Change in engine RPM didn't seem to change the tone. However, at times the tone would fade slightly and then get louder, but I couldn't correlate that to anything.
I washed the airplane for the first time 24 hours prior, so I'm wondering if I maybe got something wet in the panel, or possibly did something to an antennae when I was cleaning? Or perhaps the timing of the washing and cleaning is coincidental?
Any thoughts or ideas out there on either the tone or the 430 messages? Thank you!
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