B717 First Officer reported a landing gear indicating light malfunction during gear extension. Flight crew confirmed that all gears were down and landed safely.

Narrative

The event occurred ZZZ1-ZZZ into ZZZ on the visual XXR. Around 2;000 feet we extended slats; flaps 13; and speed was 180. I called flaps 18 and gear down around 1;800ish. When the gear came down; the left main and nose wheel gear lights were illuminated green and safe. The right main gear would not illuminate. The configure page showed all three down and green. We tested the annunciator panel for a burned out light; when shortly after we received the level 1 PSEU (Proximity Electronics Unit) FAIL. We were just about to cross ZZZZZ when we decided to go-around to allow ourselves more time to troubleshoot and decide the safest course of action. We advised ATC out of an abundance of caution. We ran several checklists; executed a low approach for tower to check our gear. Tower told us all three were down; we got ourselves situated to land on XYR into ZZZ. We landed safely without issue and had the fire trucks check us out. Once we got the green light; we taxied to the gate to meet maintenance.