Narrative:

Last week; when I had gone to brookhaven; I did a cursory test of both navs by tuning in the VOR and an ILS on an airport I was crossing on my garmin 30SL that was just installed. Everything checked out perfectly and matched up which I felt was a good test for doing an approach in actual conditions. On sep/xa/08; I wanted to do some approachs in actual conditions. I was in solid IMC on my first approach and was getting discrepant information between navigation #1 and navigation #2. Neither gauge had flags; so I couldn't tell which one was wrong. Approach calls me and asks me if I am picking up a localizer. I reported back; yes I am but I am getting discrepant information between my navigation #1 and navigation #2 and I am working on correcting the problem. Approach then gave me an advisory that I was west of the approach course so I decided to discard navigation #2 and fly by navigation #1 only and I advised approach that I have the discrepancy resolved and correcting my course. Navigation #2 had me east of course. A few mins later approach must have seen I was ok; and switched me over to tower. Up until that point I didn't know which gauge to believe! GS on both matched up perfectly on this approach. Right around the FAF brenz; I started getting a flag on navigation #2 on the localizer only (GS still worked and not flagged); so I continued to use navigation #1 as my primary guidance since the flag in my mind indicated gauge was getting faulty information. To further confirm navigation #1 I was also using the CDI on the garmin 430 that is supposed to be only for guidance and since both navigation #1 and the GPS matched on the localizer. Strangely enough; the localizer would act like it was working even though the flag symbol was displayed. GS pretty much worked the entire time in spite of the flag popping up as well. Talk about crazy discrepancies. Flew today sep/xa/08; avionics guy came out today; reseated the radio; checked the dpin jiggy in back of the panel behind navigation #2; reseated that; all 'indicated ok' on the ground with a VOR check. So; knowing communication #2 is still suspect and it was IMC conditions; I planned strictly using navigation #1 for my navigation and figured to mirror navigation #1 with communication #2. VOR picks up; and passes the check; but unfortunately today; no ILS; and no GS and no flags! Called him back and he thinks it may be the radio not sending out a good signal. I don't know about radios; but there was no flag indicator on the localizer on the radios; it idented and showed the correct identifier; so in my mind; it makes me think it's something between the navigation #2 gauge and the radio not wired right? Today; something new; no to/from flag on navigation #2 for the VOR; which was working yesterday. I will fly the plane to the shop on monday so they can bench test the gauge and radio. Callback conversation with reporter revealed the following information: reporter advised the unit had been installed incorrectly. One lead from the management unit to the CDI display was not secured properly. He reports it is now working satisfactorily.

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Original NASA ASRS Text

Title: BE23 PLT REPORTS GARMIN 30SL FAILED TO SHOW FLAGS WHEN DISPLAYING FAULTY INFORMATION.

Narrative: LAST WK; WHEN I HAD GONE TO BROOKHAVEN; I DID A CURSORY TEST OF BOTH NAVS BY TUNING IN THE VOR AND AN ILS ON AN ARPT I WAS XING ON MY GARMIN 30SL THAT WAS JUST INSTALLED. EVERYTHING CHKED OUT PERFECTLY AND MATCHED UP WHICH I FELT WAS A GOOD TEST FOR DOING AN APCH IN ACTUAL CONDITIONS. ON SEP/XA/08; I WANTED TO DO SOME APCHS IN ACTUAL CONDITIONS. I WAS IN SOLID IMC ON MY FIRST APCH AND WAS GETTING DISCREPANT INFO BTWN NAV #1 AND NAV #2. NEITHER GAUGE HAD FLAGS; SO I COULDN'T TELL WHICH ONE WAS WRONG. APCH CALLS ME AND ASKS ME IF I AM PICKING UP A LOC. I RPTED BACK; YES I AM BUT I AM GETTING DISCREPANT INFO BTWN MY NAV #1 AND NAV #2 AND I AM WORKING ON CORRECTING THE PROB. APCH THEN GAVE ME AN ADVISORY THAT I WAS W OF THE APCH COURSE SO I DECIDED TO DISCARD NAV #2 AND FLY BY NAV #1 ONLY AND I ADVISED APCH THAT I HAVE THE DISCREPANCY RESOLVED AND CORRECTING MY COURSE. NAV #2 HAD ME E OF COURSE. A FEW MINS LATER APCH MUST HAVE SEEN I WAS OK; AND SWITCHED ME OVER TO TWR. UP UNTIL THAT POINT I DIDN'T KNOW WHICH GAUGE TO BELIEVE! GS ON BOTH MATCHED UP PERFECTLY ON THIS APCH. RIGHT AROUND THE FAF BRENZ; I STARTED GETTING A FLAG ON NAV #2 ON THE LOC ONLY (GS STILL WORKED AND NOT FLAGGED); SO I CONTINUED TO USE NAV #1 AS MY PRIMARY GUIDANCE SINCE THE FLAG IN MY MIND INDICATED GAUGE WAS GETTING FAULTY INFO. TO FURTHER CONFIRM NAV #1 I WAS ALSO USING THE CDI ON THE GARMIN 430 THAT IS SUPPOSED TO BE ONLY FOR GUIDANCE AND SINCE BOTH NAV #1 AND THE GPS MATCHED ON THE LOC. STRANGELY ENOUGH; THE LOC WOULD ACT LIKE IT WAS WORKING EVEN THOUGH THE FLAG SYMBOL WAS DISPLAYED. GS PRETTY MUCH WORKED THE ENTIRE TIME IN SPITE OF THE FLAG POPPING UP AS WELL. TALK ABOUT CRAZY DISCREPANCIES. FLEW TODAY SEP/XA/08; AVIONICS GUY CAME OUT TODAY; RESEATED THE RADIO; CHKED THE DPIN JIGGY IN BACK OF THE PANEL BEHIND NAV #2; RESEATED THAT; ALL 'INDICATED OK' ON THE GND WITH A VOR CHK. SO; KNOWING COM #2 IS STILL SUSPECT AND IT WAS IMC CONDITIONS; I PLANNED STRICTLY USING NAV #1 FOR MY NAV AND FIGURED TO MIRROR NAV #1 WITH COM #2. VOR PICKS UP; AND PASSES THE CHK; BUT UNFORTUNATELY TODAY; NO ILS; AND NO GS AND NO FLAGS! CALLED HIM BACK AND HE THINKS IT MAY BE THE RADIO NOT SENDING OUT A GOOD SIGNAL. I DON'T KNOW ABOUT RADIOS; BUT THERE WAS NO FLAG INDICATOR ON THE LOC ON THE RADIOS; IT IDENTED AND SHOWED THE CORRECT IDENTIFIER; SO IN MY MIND; IT MAKES ME THINK IT'S SOMETHING BTWN THE NAV #2 GAUGE AND THE RADIO NOT WIRED RIGHT? TODAY; SOMETHING NEW; NO TO/FROM FLAG ON NAV #2 FOR THE VOR; WHICH WAS WORKING YESTERDAY. I WILL FLY THE PLANE TO THE SHOP ON MONDAY SO THEY CAN BENCH TEST THE GAUGE AND RADIO. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER ADVISED THE UNIT HAD BEEN INSTALLED INCORRECTLY. ONE LEAD FROM THE MANAGEMENT UNIT TO THE CDI DISPLAY WAS NOT SECURED PROPERLY. HE REPORTS IT IS NOW WORKING SATISFACTORILY.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.