Note: It is recommended to carry out diagnostics of the fuel pump at a specialized service station.
To diagnose the fuel pump:
- turn off the ignition;
- disconnect the high pressure fuel line;
Warning: Even when the engine is not running, some gasoline will leak out because the fuel system is under pressure.
- if gasoline does not flow out, turn on the ignition;
- if after this petrol does not flow out, check the pump relay fuse. If the fuse is faulty, replace it. If after this the pump works, find the cause of the fuse failure;
- if the pump is not working yet, check with a tester whether voltage is supplied to the diodes. If you do not have a tester, contact a service station;
- if voltage is supplied, it means the pump is faulty or the cable is broken;
- if the pump is working, but fuel does not enter the distribution line, it means that the fuel filter is clogged or one of the fuel lines is damaged;
- If after all checks the pump does not work, remove it to check and replace if necessary. A special tool is required to remove the pump.
The electrically driven fuel pump is energized via a relay in the engine compartment. The pump only operates when the engine is running or when the ignition key is turned to the engine start position. A second relay is activated when the engine is not running and the ignition is on. The relay interrupts the electrical current through the interlock circuit in the engine control unit. This prevents gasoline from leaking out, for example after an accident.