The following article discuss about 1999 Chevrolet Corvette Fuel Pump Relay Control Circuit including circuit description, condition for running the DTC (Diagnostic Trouble Code), condition for setting the DTC, action taken when the DTC sets, conditions for clearing the MIL/DTC, diagnostic aids, etc. When you turn the ignition switch to the on position, the PCM activates the in-tank fuel pump. The fuel pump remains on as long as the PCM receives reference pulses from the electronic ignition system. If there are no reference pulses, the PCM turns the fuel pump off after about 2-3 seconds. The PCM controls the fuel pump relay by applying B+ to the control circuit via an internal switch called a driver.