It’s something like win-ctrl-f23

(Despite the physical buttons having been missing for a long time on regular keyboards, there are still scancodes for f13-f24)

For what it’s worth too, the Windows “Powertoys” utilities have always been able to remap it.

The great news is we have Zac (JerryRigEverything) to test exactly that:

https://youtu.be/yk_u9fbkoKM

Towing at around its maximum rating in the cold, the range was indeed below 100 miles.