Brake booster pump, stays running constant

[SeanWN86]

So I was bleeding my brakes, 1st rear brake went fine. But when doing the second, the pump stays running constant. It will not stop.

It sounded fine when I first started. Nice and strong for 4-8 seconds after turning key to ON, and stop. But it started sounding weak when I was doing the second. Realizing that using the pump during the first, and that the truck hasn't run for almost 3 weeks, maybe my battery was low. Yup, have ~6v at the terminals. Can't start the truck, and of course nobody is here to jump it. So I'll be getting a replacement, charger, or wait to jump,p it.

But in the mean time, the pump just running constant; could that be caused by low voltage? Or am I ****ed and my brake master cylinder, or brake booster pump assembly, is bad?

 

[AuSeeker]

I really don't know the answer to your question, but I think with the low voltage the pump can't build up the pressure properly and is why the pump keeps on running, so I would see what happens when you put a good/new battery in it, which should reset everything, also deliver the proper voltage to the pump and then start to worry if the motor is still running continuously, no need to worry yourself until everything else is right and you still have this issue.