Symptom: a Honda Accord car, paroxysmal start after the start gradually turn off, start again difficult or can not start.
    Troubleshooting: first check the ignition system in the event of failure, are normal, and then in the fuel line in the oil pressure gauge, in the pump connector in parallel with a 21W test lamp, the pump pump oil supply status and work conditions for simultaneous inspection The The key screwed to the "ON" position, the oil pressure rose to 270KPa, try light, start the engine, try light does not shine, start the engine, work properly. Turn off the key again when the key to "ON" when the fault occurs, the test light does not shine, no change in oil pressure gauge. The static pressure of the system is generally higher than the working pressure, so when the key is screwed to the "ON" position, the oil pressure should rise and the fault is suspected to be on the PGM-F1 main relay.
    Check the PGM-F1 main relay without removing the plug. Connect the light-emitting diode between the positive pole of the battery and the 8th pin. After the key is turned on several times, the LED is bright, the light-emitting diode is bright, the test lamp and the oil pressure gauge are not changed, Identified as PGM-Fl main relay failure, after its replacement after several test failure disappeared.
    Fault Analysis: The PGM-F1 main relay consists of the ECM main relay and the oil pump relay. When the key is screwed to the "ON" position, the ECM main relay is engaged for powering the computer, injector and pump relay. The computer receives the output signal of the ECM main relay, the oil pump relay 8 feet to send 2S ground signal, so that the pump relay pull 2S, for the fuel system pressure. In the 8th foot and the battery cathode connected between the light-emitting diode, is to check the ECM main relay and the computer is working properly, the pump relay is triggered signal.
    When the pump relay fails, the remaining pressure in the system allows the engine to start, but as the oil pressure decreases, the engine is gradually extinguished. As the pump relay work is not stable, and then start the fuel shortage or not oil, so that the engine re-start difficult or can not start the fault.