Having a really weird issue with my 21 Vulcan S

I was in hospital for a shade over three weeks, so my bike was sitting in the garage.

Kick stand down, clutch out, I try to start the bike. Ignition is fine, lights all activate and I get a "click click click".

I figure it must be the battery, so I put a multimeter on it and get 12.6v.

I pull the clutch, kick stand down, 'click click click'

I pull the clutch, kick stand up, bike starts, little slow on turning over but starts with an engine light.

I check the engine code and I get a code 62, which lists pre throttle body, but the bike seems to run fine.

The only people who have done any work on the bike is Kawasaki.

Any ideas? Because I'd really like to avoid getting financially gangbanged by Kawasaki to check it out.