mooney2201 Posted April 28, 2018 Report Posted April 28, 2018 Gear down light is dim even with position lights off...manual says CR24 (assy A2) is open...any idea where that part is Quote
kortopates Posted April 28, 2018 Report Posted April 28, 2018 1 minute ago, mooney2201 said: Gear down light is dim even with position lights off...manual says CR24 (assy A2) is open...any idea where that part is No, but find it on the electrical schematic. It will show location as well. Quote
N231BN Posted April 28, 2018 Report Posted April 28, 2018 I believe they are referring to components on the circuit board inside the annunciator box. Quote
mooney2201 Posted April 29, 2018 Author Report Posted April 29, 2018 I believe your right...transistor 24 is open.Easy fix Quote
N201MKTurbo Posted April 29, 2018 Report Posted April 29, 2018 It is a diode. Depending on the year it could be in different places. In my 77 J it is part of the lighting harness. You will find it near the panel light potentiometer. Quote
bradp Posted April 29, 2018 Report Posted April 29, 2018 You didnât recently install all new LED Nav lights did you? 1 Quote
mooney2201 Posted April 30, 2018 Author Report Posted April 30, 2018 I did just install led lights Quote
carusoam Posted April 30, 2018 Report Posted April 30, 2018 Hmmm... Sounds like something isnât recognizing the LED lights.  When the anunciator is looking for the standard lights? My 94 anunciator...auto dims the green gear light to an unreadable level when the nav lights are on... Other goofy old ways of perma-dimming lights in Mooneys were to use 24v bulbs in 12v applications... PP thoughts only... Best regards, -a- Quote
mooney2201 Posted April 30, 2018 Author Report Posted April 30, 2018 Always something...Cha ching Quote
bradp Posted April 30, 2018 Report Posted April 30, 2018 OHereâs what I sent a couple of Mooney spacers who asked.  I have limited direct experience with this one save I kept my tail Nav incandescent in the circuit because I anticipated the gear indicator  light would be an issue. The ground path through the LEDs is altered.  Thereâs a dual ground path through the gear indicator.  When the Nav lights are off the gear indicator grounds through that circuit.  When the Nav lights are on the gear indicator will through an alternate circuit and a resistor. With the LEDs the grounding through the Nav lights off circuit is altered in some way.  I believe someone had previously indicated a resistor was needed in to restore the normal behavior of the two ground paths for the gear indicator.  This thread may help.  Quote
carusoam Posted April 30, 2018 Report Posted April 30, 2018 Sounds similar to instrument panel light dimming with all LED replacements.... that solution was leave one regular bulb in place... PP thoughts only, not a mechanic... Best regards, -a- Quote
N231BN Posted April 30, 2018 Report Posted April 30, 2018 If you know the wattage of the gear bulb it would be easy to calculate the needed resistor. An alternate method would be to install a small toggle switch on the ground. Then you can use your LED lights during the day and still see your gear indicator. Quote
ArtVandelay Posted April 30, 2018 Report Posted April 30, 2018 14 hours ago, carusoam said: Hmmm... Sounds like something isnât recognizing the LED lights.  When the anunciator is looking for the standard lights? My 94 anunciator...auto dims the green gear light to an unreadable level when the nav lights are on... He said they are still dim with his nav lights off? Quote
carusoam Posted April 30, 2018 Report Posted April 30, 2018 TJ, what I am going with... LEDs + traditional dimming = unpredictable behavior.... Â i like using as many lights as i can. Even in daylight... The way the Mooney anunciator works, it dims the anunciator panel with the position lights on... Â There is probably something measuring resistance or voltage and causing the dimming... Â just a WAG on my part... There is a wiring diagram in the MM that may give a hint to the hows and whys... Best regards, -a- Quote
ArtVandelay Posted April 30, 2018 Report Posted April 30, 2018 BTW, Iâm going to be selling my 78J annunciator if you need one, for whatever reason, mine didnât dim and the gear down light is white. I realize after looking at it closely, the reason itâs white is the green cellophane has been bleached clear over time. Quote
mooney2201 Posted April 30, 2018 Author Report Posted April 30, 2018 Made a few calls today, will know more tomorrow.. 19 hours ago, carusoam said: Hmmm... Sounds like something isnât recognizing the LED lights.  When the anunciator is looking for the standard lights? My 94 anunciator...auto dims the green gear light to an unreadable level when the nav lights are on... Other goofy old ways of perma-dimming lights in Mooneys were to use 24v bulbs in 12v applications... PP thoughts only... Best regards, -a-  Quote
jrp Posted May 21, 2018 Report Posted May 21, 2018 Folks,  I'm also having this problem.  I switched to LED position/strobe lights several years ago and annunciator worked fine (gear down light would dim when panel lights were on and be plenty bright for full daylight, when panel lights would be off).  In the last year or so, some of the annunciator lights (gear in partucular) started being intermittent.  After resesraching, I sent the annuciator to Avionics International for overhaul, as suggested by my shop.  They did their normnal overhaul and sent back, and the gear light was permanently dim, with panel lights on or off.  I talked extenmsively Avionics International (both Ken Snowden and Ken Pethe, CEO) who were super diligent, and earnestly tried many things and lots of bench tests.  Sadly when the sent the unit back to me again, the gear light remains permanently dim.  I'm trying again as I head into this years' annual.   Keen to hear of any other ewxperiences on this issue.   Thanks.  JP Quote
ArtVandelay Posted May 22, 2018 Report Posted May 22, 2018 Did you turn of the nav (position) lights? 1 Quote
carusoam Posted May 22, 2018 Report Posted May 22, 2018 Some annunciators auto dim when the nav lights are on... If something got miswired.... Expect that something is delivering voltage to the auto dim function... Best regards, -a- Quote
CaptainRon Posted September 20, 2021 Report Posted September 20, 2021 I just put WAT LED wingtip lights, tail lights, belly, LL. Overhauled the annunciator panel with IAI and now I am seeing this issue with gear light dim,. Can anyone give me more details about the shunt resistor or solution used? Thanks World. Quote
N231BN Posted September 20, 2021 Report Posted September 20, 2021 There are four wires connected to the load side of the nav light CB switch, three for the lights themselves and one smaller-gauge wire which is the ground for the Gear Down light. It needs to be disconnected from the CB switch and connected to ground in some fashion. I prefer to connect it to a mini toggle(labeled DAY/NIGHT) and then to ground so you have manual control of the dimming. Closed(grounded) is bright, open is dim. 2 Quote
PT20J Posted September 20, 2021 Report Posted September 20, 2021 This happens whenever ALL the incandescent lamps are replaced with LEDs because of the way the Mooney annunciator panel is designed (Ref section 24-39-06 of the M20J Service and Maintenance Manual). Somewhere on MS there is a post with a design to add a relay to make it work as originally designed. Skip 1 Quote
carusoam Posted September 21, 2021 Report Posted September 21, 2021 Makes a ton of sense to have a switch for Day/night operationsâĤ Many people fly around all day with nav lights on for better recognitionâĤ. The risk of doing thatâĤ Mooney decided to dim the annunciator panel automatically, to near unreadable, under these conditions during the dayâĤ PP thoughts onlyâĤ not a mechanicâĤ Best regards, -a- Â Quote
CaptainRon Posted October 8, 2021 Report Posted October 8, 2021 On 9/20/2021 at 12:47 PM, N231BN said: There are four wires connected to the load side of the nav light CB switch, three for the lights themselves and one smaller-gauge wire which is the ground for the Gear Down light. It needs to be disconnected from the CB switch and connected to ground in some fashion. I prefer to connect it to a mini toggle(labeled DAY/NIGHT) and then to ground so you have manual control of the dimming. Closed(grounded) is bright, open is dim. thanks Quote
CaptainRon Posted October 10, 2021 Report Posted October 10, 2021 (edited) There are four wires connected to the load side of the nav light CB switch, three for the lights themselves and one smaller-gauge wire which is the ground for the Gear Down light. It needs to be disconnected from the CB switch and connected to ground in some fashion. I prefer to connect it to a mini toggle(labeled DAY/NIGHT) and then to ground so you have manual control of the dimming. Closed(grounded) is bright, open is dim. _____________________________________________________________________________________________________________________________ I looked back there and sure enough four wires all white, don't want to make any assumptions maybe they are labeled someplace, but they all look the same to me. So following your description the circuit from the panel in schematics in annunciator section labeled "Gear Down Return" ,. For my 78 serial number this seems to be the wire you are talking about in the schematics. The other three wires route to tail light and the two wing tips. Having thought about all this a great deal I think the day / night switch makes the most sense. but if you wanted to keep behavior the same , what does this shunt resistor setup look like? someone mentioned there was a post but I can't find it. I'm on the 14V system.  Edited October 11, 2021 by CaptainRon Quote
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