so today, 3 areas of the car stopped working: engine shut-off, door lock control from driver's door, & HVAC; should I start with the vacuum pump itself?
RD, In your profile, please put your car info in your signature so we know what you have.
Start with a vacuum gauge on the line from the pump. Also look at condition of the vac lines and rubber fittings as it heads to the firewall and the power steering vac line.
ok thx! turned out to be one of the 4-way rubber connectors gone bad