VNAV Disengages at TOD

I put VNAV on during cruise and when I get to my TOD, it shuts itself off automatically and does not descend. I have to turn it on once again to initiate my descent. Any suggestions?

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Quite hard to see what’s wrong without a flightplan (with alts shown) and where you are on that flightplan. Can you share some screenshots?

I am in the middle of my descent at the moment, can upload some in a few minutes. I can assure you that I was at my TOD as I was watching VNAV count down to my TOD. Once I got to zero nautical miles until TOD, it shut off and did not descent.

I think this belongs in #support

Yes! Finally someone who can vouch that I’m not crazy.
This happens to me also during descent, I don’t know why.
Maybe just try to manually descend and check the the waypoints further in your descent are lower than waypoints sonner

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It is bizarre. Once I initiate it though, it descends exactly how I want it to. I am a little concerned for if I ever wake up a little late or get home late to my airplane at FL380 25 nm from my destination.

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Yes, for me it happens when I watch it desend, are you on Samsung?

Nope I am on iPad

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It has happened to me before too. Usually the issue was caused due to a disparity in the alts of your descent (i.e 25,000/ 19,000/ 9,000/ 12,000/ 5,000). This is simply because the filed STAR has a block altitude at the disparity point, and the app will always defer to the high block limit. (i.e the 12,000 alt might have a low of 7,000)

Im not sure why that happens but I assume that’s the reason the guide says don’t turn on vnav until TOD.

Hi there, does it happen with every flight?

Can you do another flight and see? Can you attach a picture of your flight plan with altitudes?

I have seen the VNAV turn off sometimes if you are lower than the next waypoint. I was cruising once at FL280 and the first waypoint in the STAR was FL300. It will turn off because it will not climb. Once you get past that spot you should be able to reengage it.

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It is not every flight. I’d say at least 60% of them, though. I am en route to FRA for FNF right now. Let me get back to you with pics.

Not going to switch VNAV on quite yet because i am stepping to FL430 in an hour or two, but after that it will be on.