You pull the handle on the dash out, the cable then pulls on a lever on top of the fuel solenoid above the injector pump. When starting the truck, then solenoid gets energized and opens to allow fuel to the pump. When shutting down, then solenoid de-energizes, cutting the fuel off to the pump. All the emergency handle does is over ride the solenoid and manually shuts the fuel down. Pulling the handle is a one time use thing, so if you want to start up again, you have to push the lever back by hand. Pushing in the emergency handle won't reset it.