Athearn Sound/DCC F units yet again

[Southwest Chief]

I was wondering if these have dimmable headlights? I think I might have dimmed mine by accident and I’d like to get them back to full intensity. But I'm not sure if they are dimmable in the first place. But lately the lights just seem a bit dim, and I know most decoders support dimmable headlights. So maybe these can too. If so, what is the function button to bring the headlights back to full intensity?

The instructions that accompany the units are not the best and do not mention dimmable headlights, or the CV that controls this feature (if it’s even a feature)

Anyway if anyone has any tips or suggestions let me know. Oh I have the Santa Fe F3 A+B 32L and 32A (and I operate them on DCC only) if this matters.