Low voltage output from 12v/100w panel

Hi, all. After a bunch of lurking here, I finally put together a small system with Renogy's "starter kit": 12v/100w monocrystalline PV and Wanderer 30A PWM CC.

After installing the system and hooking up a 12v gel battery, I took a voltage reading from the input (PV) connection on the CC and it's showing 17-20 millivolts. This seems really low - from what I understand, it should output close to the "native" 12v. Also, the PV indicator LED is not lit up.

The CC output terminal (battery side) is showing ~12.5v. The panels are in full sunlight and approximately towards the sun.

Am I misunderstanding what the input voltage should be, or could this be an issue with the panel/CC.

Would love any input. Thanks!