Do you have a schematic of your circuit?
A PNP, I don't see how this works. A NPN (emitter follower), with the collector connected to the +24, the emitter to the load, A resistor from the collector to the base (this turns it on) and the base through a load resistor to an open collector to ground switch.
But this configuration is tough if your wanting more then a few milliamps. I've used a self resetting fuse for the collector to base turn on source power (the smallest one Polyswitch had), and a FET from the base to ground, that turns this off. This was intended to act like a normally closed switch. And the FET was used to turn it off.