before I start throwing parts at it, I was hoping someone might be able to maybe point me in the direction of what could be the potential problem.

here's a little more info to give more detail to better help give a potential diagnosis; brake pads do need to be changed, front rotors, pads & calipers were all done last feb/march however the whole system wasn't properly bled due to a line with a leak - due to another person's impatience & stubbornness to let me be right, I was never able to change the line to fully bleed the system & now here we are. so unfortunately the brake system has taken a bit of a beating. now that she's back in my possession, I'd like to fix her back up - I am not so great at diagnosing issues but I am mechanically inclined & eager to learn anything that I don't already know.

I was reversing & heard a big clunk, at that point I lost all braking power so I put it into neutral & coasted forward, tried pumping the brake, tried pulling the ebrake but nothing so I put it into drive & turned to avoid a ditch - noticing at that time that I also had no powersteering, but I could still accelerate. I was able to find a spot to safely coast into where I put it into park & put blocks behind the wheels..

I need help - just not sure where to start..

 

Post your vehicle info please. year/engine/miles. Thanks

 

Also post any and all Diagnostic Trouble Codes (DTCs) from the OBDII system.

Also, are you doing the repairs yourself or is a shop doing the work for you?

 

Is this a hydro boost system? Seems unlikely since it’s a trailblazer but we need to know for sure.

1) Check if the serpentine belt was broken/thrown. If yes, spin each pulley by hand to check if any have seized and rock them top to bottom to check for play. If not, install a new belt, tensioner and idler.

2) If the belt drive is functional, the most likely issue is the power steering pump quit working. Replace it, and the pressure line off the pump.