On all vehicles with the KPVT should be on the Weapons Group 1 keybind, however it's on the Weapons Group 2 keybind.
Current control configuration on multiple vehicles
Weapons Group 1: nothing
Weapons Group 2: KPVT and coax machine gun
Includes the BDRM, BTR-60, BTR-80, GAZ-3937 Vodnik KPVT, and Hilux/Hilux Armored BTR-60.