Brake light opens when in R

[Goulet264]

Hi, I just bought a 1981 chev very recently and I avoid driving it because of a slight issue. When I put it in reverse, 2nd or 1st gear, the brake light on the dash lights up for a second.

I'd rather be safe than sorry, does anyone know what the issue could be?

 

[Snoots]

Bleed your brakes first. It could be air in the brake line at the proportioning valve.

 

[Goulet264]

Bleed your brakes first. It could be air in the brake line at the proportioning valve.

I will try this thank you!