Flysky low Rx battery warning

I just got a URUAV UV65 brushless, but when I bind it to my Flysky, it shows 0.0V for the Rx and beeps constantly, even though my HV battery is fully charged. Anyone have any idea what’s happening, or how I might fix it? I’m stumped, and googling hasn’t helped so far…

Use a fresh battery you know the voltage of. Then log Betaflight configurator as usual but plug in the fresh battery.
Check in betaflight and see If you have matching voltage.
Not the simple battery meter at the top.
Click the slider for advanced settings tab
Choose the input and battery tab (that’s not exactly how it’s worded)
Check the voltage displayed in Bf against aforementioned battery voltage to see if they match.

On a different tactic on rare occasions when I get 3 or 4 packs in with my mobula I have a similar issue with 0 rx voltage.
Try killing TX and kwad then power up kwad wait a few seconds and power on ur TX. Works for me bro

Also check TXs internal voltages are correct

Only option is probably to turn the warning for Rx voltage off.
If it’s reading 0v the sensor isn’t hooked up, that telemetry sensor is part of the RX unit rather than something fed from the FC.
If you’re feeling brave you could find what pin on the RX microcontroller chip it reads for voltage and do some tiny soldering for it.

Turning the warning off should be easier though.

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^^^^^^^^^^^^^^^^^^^ yes sir Bobnova is correct

One possibility is that betaflight thinks the cell voltage is too low. If the max battery cell voltage has not been increased in betaflight to 4.4 or 4.5v, then on a fully charged HV battery, it may think there are two cells, and 4.35/2 will trigger a low battery warning. Easy way to check - try a battery only charged to 4.1v or so. If that is OK, then that is the problem.

Yup, I was able to turn the Rx sensing from “internal” to “external”, and it works fine now. Thanks for your help. And wow, brushless 1S is a heck of a lot faster than my old brushed!