Problem with Torque pid

I have been using Torque Pro since 2012 with a "C", and now my current PiP. This has centred around calculating distance and fuel use, to produce a real-time economy value, with 2 advantages - the display is line-of-sight next to the HUD, and I show L/100km, which isn't on the dash (km/L) and buried in the shadows making it impossible to read on bright day.
For fuel consumption I have always relied on the built-in Torque pid "fuel use(trip)" and applied a multiplier to calibrate the result to match pump receipts, giving a dead-accurate result.

A couple of days ago, I put in a 200km trip, and found that the "fuel use(trip)" sensor has stopped delivering data, making my display useless. On the dash the fuel gauge still works OK, and the dash economy readout appears normal. Since then I have added fresh fuel (the first in many months over our winter, 2500km covered mostly in EV mode), and charged the 12v battery.

Torque built-in pids are "industry standard" and work on many vehicles. Toyota doesn't appear to use this one for anything, but data has always been fed to the ECU (until now). My dealer's service manager who is a Torque user so understands where I am coming from, suggests a comprehensive ECU scan, also says it is possible it is not a specific sensor, but a calculated value from other sensors - I can't quite see why Toyota would do this without then using the data in some way. Perhaps it is? I don't know what I don't know...
He also recommends against replacing an apparently working OK fuel pump, on cost grounds..

Anyone think they can shed some light on this? All donations gratefully accepted

Edit:
Solved!
All the years I've been using this stuff, but I still got caught (maybe a senior moment?)..

I acquired a Kona EV at the end of April, and spent some time getting some useful Torque gauges set up. So I created a Kona profile, linked the profile to it's own dashboard, then went through all the other settings. When I got to the OBD adapter section, with my head in "Kona EV" mode, I turned off all the fuel sensor checkboxes (don't need them on for an EV, slowing the adapter down, do I?)..
Well, yes I do, because while the dashboard can be tailored to the individual profile, Torque's settings are global, so as soon as I get back into the PiP and switch profiles and .csv files, I don't have fuel data anymore for the PiP, having turned it off while in the Kona...

Duh