NicoN

Yes, I have it

Thank you! I am also of the opinion that it is not a general problem. 1. HSI can work as a PFD, I checked the auto-revert feature a couple of months ago - IAS and altitude are the same and headings is also fine 2. you can see that the msic. Field CAN indicate the winds aloft. Nevertheless there are rumours that in general the winds aloft calculation might confuse left and right Garmin was not interested in my video but recommended to find a solution with my authorized Garmin dealer. To be honest: my "authorized Garmin dealer" was not able to complete the calibration of the GMU11. They did not even have a secret contact to a Garmin guru to find the solution We are definitely not on the latest firmware (we have 2.62). Wasn't there something that the latest firmware makes my analog NAV2 (KX155) useless? I was hoping that someone says "this problem is solved with FW xyz" or a sophisticated config value

Video to demonstrate th eproblem As you can see, I have winds aloft indication on the PFD and also TAS. The problem for the HSI is also shown

Sorry, my posting was not precise. English is not my native language. And yes - we have OAT, we see as calculated TAS on PFD; that works The Misc. Field on the PFD can display winds aloft in different flavors, such as Headwind/crosswind, windspeed and a little arrow for direction and also windspeed and driection in degress. All work fine on the PFD Same can be configured on the HSI and this time the indication of valid information does not start automatically, but only afetr appling the setting again. then I see the information I want. On top, the setting seems to be volatile; with the next flight the same problem arises - definitely not a real problem but annoying.

GI275 has an option to display a "Misc. Field" in the display of a PFD and also on the HSI. one option is to display wind/velocity in different versions I configured the HSI to display wind direction and velocity. Therefore a little block appears on the display with "360/--"; sounds fine. The aircraft is on ground, so no GPS-Speed or track and also no airspeed. But, while in the air, it did not display the wanted information - still "360/--". Then - while - flying, i configured the same setting again, and voila, now it displayed a value (no clue if correct). on my next flight - same problem again, information is displayed but non-sense. And again, problem can be solved by applying the setting again. Any ideas ? is this a known problem? i did not see that this is addressed by a higher firmware (we have 2.62)

Our A/P wants to overhaul our alternator and/or the slip clutch (?) I saw once in januaray a fluctuatiing indication of our amperemeter (rapidly moving hand, but only about 10% of the meter range). This stopped after a couple of minutes and I have never seen it again.

We have this little panel with 4 fuses in the copilots foot well. One is for instrument lighting. On top there is a C/B for the same purpose. Why?

I was asked from my partner if we (also) have an additional screen filter besides the normal oil filter. The reason for the question: In a PIPER owned by his son horrible things were found in the screen filter

I started this topic a long time ago. I simply noticed that your CDT needle did not move at all A shop diagnosed the indicator as faulty, but it was never changed. Trying to find out what to do, I simply disconnected the sensor and measured the resistance: overload. Then I shortened the wires to the instrument with master switch on - full deflection. So instrument is fine. we then replaced the sensor and CDT is working since then. My experience: during takeoff, at sea level CDT was never an issue. The needle is moving a little but never critical. The higher I climb, the more CDT is rising. I saw situation where I had to lower the power as CDT was approaching the limit temperature.

Right, we also have electrical trim but not auto-trim. So, the answer is: we need THREE servos Next question: We have 2 GI275 installed; do we ONLY need Servos (3) and a mode controller, or do we need another G5 or GI275?

I Recently changed the setting for the MISC.Field on the PFD and the HSI The PFD shows now a direction arrow and wind speed. On the HSI , I configured this MISC Field to indicate Headwind/crosswind, but this shows only two lines of dashes (in the air) The previous setting was TAS and it worked. So, I think the HSI has all necessary information it needs What is worng?

A colleague said, that the GFC500 provides vertical guidance by using the servo not direct on the elevator but using the elevator trim. Therefore he has the idea that you need 2 Servos to have lateral guidance AND vertical guidance including elevator (auto)trim. I thought you need 3

Okay, mission accomplished. Even with a newer firmware, switching between HDG and GPSS mode is not perfect. Using an external switch is way better. But the necessary details are not so easy to get. Her is what I did. 1. The switch needs to be wired to the PFD (the GI275 with ADRHS and Ap interface), not the HSI; which is nice because it is the top device 1a It needs to be a switch, not a pushbutton. The swithc connects to GND in GPSS mode, HDG mode is done when teh switch is open with a pullup-resistor. You do not need an external one. 1b I suggest, install a DPDT version, just to have something ready to drive a indicator lamp; the GI 275 has AFAIk no pin to drive a indicator lamp. 2. Find a discrete-IN pin which is not in use. 2a The discrete pins are spread over the J2751 and J2752 connector. 2b I recommend preferring the J2751 connector over the other. J2751 is the upper connector and therefore easier to access. 2c in my installation the discrete-IN on pin 62 and 63 were not in use, which makes it easier. Pins 60 to 78 are located in the upmost row and pin 60 is the rightmost (easy for people like me who have problems with numbers greater five ) 3 one pin from your switch needs to be installed in location 62 or 63. 3a make sure the pin is inserted all the way (it should not be shorter than the others) 4 the other wire from your switch can be connected to the backshell from your connector or to one of the "Aircraft ground"-pins not in use. But this is way more complicated (number greater five, you know !) 5 Next start your PFD in config mode and go down to DIAGNOSTICS - DISCRETE IN 5a There you should see something happening when flipping the switch 6 NExt go to your autopilot settings (it is way down in the INTERFACES menu) and 6a select DISCRETE instead of BUTTON 6b select the appropriate DISCRETE IN pin 7 leave the menus and power down both GI 275 7a wait 30s without power 8 power up in normal mode 9 You should see your heading bug changing from full to hollow if you flip your switch 10 install the switch. 10a I recommend to install it with the plunger to the left ( to the PFD) indicating HDG mode on and right (to the GNS430 or so) indicating GPSS. Have fun; maybe someone finds that helpful A word to the HD-pins for the 78 pin D-SUB: I was not able to find the turned pins which need this crazy expensive crimping tool. Instead, I found only those stamped ones . They can be crimped with the cheap crimping tools offering an option fro D-Sub. But it takes a good portion of experience before you make acceptable pins which can be inserted correctly. So, under all circumstances, use the turned ones!!!!

Oh yes! GI 275 and GNS430W are playing in a team. This works already. At the moment we are using the touch button on the PFD to switch between HDG mode and GPSS. But you can also put this function to an external switch.

Thank you. My posting was not precise enough. The "pull to ground" is a typical feature of all microcontrollers. INternal pullup drwas the pin to "high". If you short it to GND - fine. Both Gi 275 have some free Discrete IN- pins free for use. So, the question is - on which device do I use/wire the switch? On the PFD? Or on the HSI?

I want to have the external switch to toggle between GPSS and HDG. I found all options hpw to configure. For me the question is: On which device do I have to connect the switch to one of the Discrete inputs? PFD ? sounds logic as the toggling happens here and the PFD has the AP interface I think it is a switch between Discrete in and GND

We have a M20k with the trim switch in the left yoke horn. Also there is the MIC-Button, trim interrupt switch and we want a AP-disconnect switch. I am looking for a littel box to assemble on top to have more space for all the switches. Is there a 3D CAD model available or a pre-frabricated box? Google is PITA if you do not have the correct words to serach for

No. We still have the same problem. The GI 275s seems to work perfect - no error messages, no aligning. The heading/compass is stable and super precise, but the calibration was another nightmare with our installer. Finally we did it on our own. Last weekend I had 2 flights in F120 for 4 hours - and believe it or not: HDG mode was perfectly working at cruise altitude and failed again in low altitudes. I tested it several times and HDG mode was working with manual HDG changes and also with GPSS activated. When it was working I reached under the panel and the tray was really cold. So, maybe we have a temperature problem. I quickly made an extension cable to operate the computer off the tray, but did not try it in real life so far. Another question: has someone a schematic of the boards inside the computer available? I have the service manual but this ends always with "replace unit". For me, the upmost board drives the heading function, the middle seems to be responsible for NAV mode and the lower seems to have some power supply function and the power transistors for the motor.

I joined a Ownership for a 1980 M20K in 2018; right after all 6 cylinders had been replaced. Analyzing the old logs from our EDM830 clearly showed, that the aircraft was flown often hot if not too hot with CHT over 400°F for a longer period of time. We came along to fly LOP to save the engine's life forever. Since then we are donig this; flying LOP with 58-65% power and CHTs never over 390; in cruis we have TITs of ~1535 and FF 8.8-9.2 gals. GAMI spread is also fine Now, again 2 cyl are with low compression. Even though the exxhaust valves are looking fine. The cylsa are loosing pressure via the valves and also into the crankcase. In-place-lapping improved one cyl and had no impact on the second. Now, the shop says, our problmes are caused by flying LOP!! and he sees those problems more and more often as people flying LOP and especially in TC Mooneys and Cirrus. Okay, what to do? If Mike Busch is right propagating LOP with lower CHTs then we made everything accordingly. But if not?

That looks exactly like ours when it broke

INteresting. In fact we still have some steam gauges installed. And I don't think that they changed something with the installation of the GI275

Correct. This was an issue when the plane came back from the installer of the GI275s: They removed a DG hooked to the C21 (NOT HSI!!!!!) And obviously they did NOT change the previous jumpering . It took me a while to convince the installer that the GI 275 is "talking" always HSI and not DG. After changing that (but where exactly) the hdg mode worked just fine. That is why I am searching for the problem in the C21 and not in the wiring itself So, the question is where the wires from our GI275 really go - directly into the 1D772? Or is something in between (a magic box?). After a couple of flights my co-owners started telling me that the HDG mode is failing. As I wrote: - the ground test is always fine - even in flight the hdg mode seems to work at least for a while - I tested the hdg mode even while on ground with external power for 30 minutes (!) moving the hdg bug left and right - fine! What I cannot test on ground is if engine vibration has some negative impact. That's why I am trying to understand the vibration test. Can the diagnostic logs tell me more? So far I could not check them. Some seem password protected.

Oaky, thank you. I forgot to say that NAV-Mode always works fine - forever. It is only heading mode which sucks. The C21 computer has a stack of 3 PCB. On the upmost Board, 8 caps (looking like grenades have been replaced. The rest not, as someone invested a lot of work in placing the original parts with their values facing down. AFAIK the C21 system is only the computer in the panel. - the motor is always working - I do not see any error messages - NAV/APPR work - wings level function is always perfect So, I think it is really a problem of the heading part. AFAIK, we only have the C21 flight computer 1D772 which is driven with the signals from the GI275 No transformers, no Radio-coupler I have the service manual and I am still not sure whichCD-xxx is where. The 1D772 has only ONE 37pin D-SUB connector - nothing else Is it labeled as CD-186 in the manual? Where is CD-175 or CD-194? According to the different manuals ist should be Pin 17 on CD-175 where the signal for Hdg comes in. But it could also be Pin 14 /CD-186

Our GI275 drives a Century 21 A/P. the wiring semms to be correctfor me. Basically it does what is expected. on ground, i can move the heading bug left or right from the lubber line and the control wheel starts turning. Same if I am taxiing; the control wheel moves if i change direction I did this a thousnd times: - In the ghangar - taxiing on the airport After take-off, it normally works also, but after 10 or 15 minutes, the A/P does not follow the Hdg bug any more. It simply continues flying the last heading. Whatever I do on the hdg bug - nothing happens; It keeps the wings level perfect but tha's it. Yesterday I was doing test turn using the hedg bug. and I think i had a moment where A/P stopped turning, returned to a wings level atttude After landing and waiting a couple of miuntes it worked again We already had an echange of several capacitors on the board ( It hink not all). It is the same situation, not better not worse Now the question: Can a failed vibration test be the reason that the heaidng mode quits (i.e. the GI 275 stops siganlling to the A/P)? I know, that sounds crazy

I recently treid to run the vibration test for our GI275 (double). I have never seen an exact procdure of how to do it. The screen said something to run the engine at max power for an extended period of time. - with max power, i easily exceed the 100% mark - with reduced power close to 100% it runs fro a coule of seconds. But I did not see a clear passed or failed sign. Weird. Has someone more information, especially what happens if the vibration ets is considered as failed? See my other posting about our problem with a century 21