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G3X LRU firing landing lights during power up?

TOGApwr

I'm New Here
Helping a friend track down an annoyance. Every time his build in progress is powered up, the landing lights activate for about 5 seconds and the mode varies unpredictably between solid or wig wag.

One powerup it's solid, next solid, next wig wag, anpower upside? After 5 seconds it follows the switch position.

I've tried the config page, switch positions, etc. No change. Any advice on how to not blind the ramp during night power powerups?
 
That's some pretty unique wiring. I use both power inputs for my G3X system, one from the Main battery and one from the Aux battery. Neither is directly connected to the landing lights, which are controlled through a separate switch and only illuminate when the dedicated landing light switch and the Main battery switch are on.
 
Perhaps you can post a wiring diagram to clarify what's involved here? :)
 
Perhaps you can post a wiring diagram to clarify what's involved here? :)

Sorry folks, I will upload as soon as able. I'm the second hand assistant in the mix and don't have direct access to the materials. That would have been smart to upload first thing....

Expect further information: Saturday... Time now: Today.
 
Are the lights controlled by a GAD 27 or VPX LRU's?

I got my hands on the diagrams this weekend. It is powered by the GAD27 it appears. The panel switch provides input to the g3x and gad27 so their logic can run and output the power as appropriate to the lights.

A new discovery... we think it's in the wig-wag logic. For context, their setup includes an auto-wig-wag feature programmable in the g3x, and we had it enabled above a certain airspeed. The logic was that if the panel switch was on, the gad27 provides solid power below 80 knots (final, to/ld, initial climb) and wig-wags automatically above 80knots (cruise climb, pattern, etc). Panel switch off = lights off.

Now, we disabled that auto-feature and the power-up-burst doesn't occur anymore. This unfortunately denies the use of wig wag as its installed now, though.

Personally, I think when the Gad27 wakes up, it's sending power until it *realizes* that the circuit should be off. I don't know if this is due to the gad not receiving air data immediately (because that too is firing up), or if the gad operates as *on* until otherwise instructed (seems unlikely), etc. Just my thoughts on it. I'm leaning toward software being the issue. We're waiting to hear from Garmin.
 

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When I had the G3X setup to control wig wag based on speed my lights would wig wag for 5 sec on system power up. I no longer use the feature and they no longer come up. I would imagine the LRU runs the lights like it thinks until some input tells it the speed or the CAN bus is up or ?
 
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