No break light when applying rear foot brake, is this the switch or something involving the ABS system.

 

probley the switch but could be a wire or something but do not think it would be in the ABS system at all

 

The rear brake switch going bad is a fairly common issue.

 

When changing switch on rear brake, does air really get into brake lines or is it just a chance for air? I'm trying to decide weather I want to do it or have moco do it. I do not know anything about how ABS systems work!

 

should not let air in , alittle fluid should come out but if you find it is the switch have a new one ready to go right back in , don't let it set with the switch out . it will drain the system