I just purchased a used Sporty (private purchase) and I noticed something weird with the turn signals.

Both front sigs have 2-connector bulbs.
The right-rear also has a 2-connector bulb.
The left-rear has a 1-connector socket, and the bulb is missing.

When I turn the ignition on, both front signals and the rear-right turn on as running lights. Rear-left doesn't turn on because... obviously... no bulb.

When I turn the right flasher on, all 3 bulbs just stay lit. And the right-turn indicator does not come on.

When I turn on the left flasher, the front-left signal operates correctly but the rear-left doesn't (again, no bulb). The left-turn indicator light also works correctly.

Before I take it to a stealership, I was wondering if there was anything I could do to troubleshoot myself. I'm pretty good with electronics (and have tools). But I've never worked with HD electronics before, nor have I worked on bike electrics newer than 1976. Just looking to be pointed in the right direction, I guess.

Thanks in advance!