The Auto Pump Timer limits the duty cycle of the 12 volt Auto Pump to
1 hour running and 1 hour "OFF". Normally the pressure switch on the
Auto Pump turns the pump "ON" when it senses a low pressure and turns
the pump "OFF" when the pressure has recovered. If a failure in the
vehicle's air system creates a high leakage, the pump will run
continuously. This continuous running can overheat the pump and cause
excessive wear. The Auto Pump Timer limits the run time to 1 hour and
provides a 1-hour cool-down period between operating cycles. The timer
does not interfere with the normal operation of the pump and its
pressure switch
