Go on. I do not own a RGB backlight display. Regular backlights are just simple LEDs with current limiting resistor.
Typical backlight currents on a 16x2 would be 20mA. This means the resistor would be about 100R for a white LED. 1k0 would be very dim.
Most 16x2 pcb have a footprint for the backlight LED resistor. You should be able to find it by following the copper traces. Some modules have 0R resistors mounted. These need an external resistor to limit the current.
RGB backlights would have separate resistors for R, G, B LED.
David.