Mine is a 2019 650XT Adventure . I can add some pictures to what everyone else has already said. The connector itself is very well hidden and, IMO, all but impossible to access unless you have the tank off, at the very least.
Here's the overview shot with the connection to the OEM grip heaters. Most of the connector you see here is the female end of the OEM grip heater harness. I have an aftermarket horn removed which is why part of the crash guard is removed.
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I put the factory plug back on for this pic. Obviously, it has been detached from the bundle that it was taped to and pulled back to the side.
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Connector with the factory plug off.
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This shot gives you a better idea of just how far inside the bike the connector is. From the factory, it is taped up very tightly, pretty much around the very end of the connector, to another bundle above it. It was almost camouflaged by the black tape holding it against the black wiring bundle. I never actually saw it until I had the tank off. Also notice that when it's in its original factory position it is almost in the very center of the bike. You can see by its relative position to the forward cylinder's intake just how far inside the bike it really is.
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This just shows how it looks when it's connected to the OEM harness.
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