I can't tell you what the codes mean. But there's nothing you could alter or damage during a simple lever change... Except the clutch safety switch.. and brake lever switch.
Not difficult, but they need to be in the proper locations to operate. I have a link below of the schematic for the clutch and brake lever assemblies. The switches I'm talking about is part #12 and part # 6. Bottom right of the switches you'll see a plunger.. that's the part you need to be sure is in alignment.
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You can try to clear the code. DO NOT attempt to start the engine, you're only allowing the bike's ECU time to self-correct. Turn the ignition switch on, let the digital dash go through it's deal, and after 10-15 seconds, cut the ignition back off. If by chance you set off a code that's no longer a problem. The bike should clear the codes you're seeing. You'll know if it worked, when you start up the engine, and the check engine light is off, and the code is cleared. Good Luck.