Main Motorcycle: Thruxton 1200R 2016
Join Date: May 2009
Location: Melbourne, Australia
The official wiring diagram for the heated grips is a complete mess, and it duplicates information for different connectors so it's difficult to diagnose problems.
According to the wiring diagram the heated grips button shorts the power wire to ground on the left grip to detect actions, but who knows if that's another mistake in the diagram or not...
The ECU does have two connectors, one for right, one for left, so my guess is that the code you see is indeed an error that is either reporting it as open-circuit, or as a short.
If so, it means you've broken the right grip heater circuit. This is the one that will always break most often because it has the twist-grip, and the wires can get trapped, worn through, or pulled apart.
I'd start by taking the right grip tube off and see if the wires are still connected inside the handlebar tube, and make sure the wire from the grip down to the connector is damaged.
I doubt very much that it's related to anything you've done on the display or settings.
Bike with a few things added, such as... me. I prefer riding my bike to bragging about the chromed rear foot-pegs. Does that make me strange?