Hey guys, I just noticed an issue over the past couple of weeks wherein hard braking causes a loss or power steering (not completely, but noticable heavier) and swerving. Additionally, turning on the air conditioning and braking at the same time causes stalling. It seems like an issue with the drive belt, considering all of these systems run off of it. How would I go about diagnosing the actual issue?

 

For starters:
Test the vacuum booster (behind the master cylinder) for a vacuum leak.
Also where the hose connects is a one-way check valve. Test that too.
Look for leaks/cracks/disconnected of all vacuum lines.