It receives positive current through the fuel pump relay (chapter Electrical equipment). The interlock circuit ensures that the pump is switched on only if the engine is running. The relay receives information about the engine running from the control unit. The interlock circuit should not allow a fire to occur due to a gasoline leak as a result of an accident.
Here it is checked whether the fuel pump supplies petrol. To do this, the recirculation hose (2) is disconnected at the connection point. Put the hose on the fuel supply line (1) and lower it into the container.
Six-cylinder engine:
- 1 - recirculation pipeline;
- 2 - fuel supply line;
- 3 - fuel pressure regulator.
Troubleshooting an Electric Fuel Pump
First of all, check the fuse (chapter Electrical equipment). If it is ok:
1. Sometimes you can listen to see if the pump is working: listen under the car at the height of the fuel tank to see if the pump comes on briefly when your assistant turns on the ignition.
2. If you can hear the pump running, it is probably OK. If you don't hear anything, check to see if fuel is being supplied:
3. Remove the fuel supply or recirculation line and place it in a container.
4. Even when the engine is not running, some fuel should come out, since there is a certain residual pressure in the fuel system.
5. If not, have your assistant operate the starter.
6. The fuel pump should now be delivering fuel.
7. If this is not the case, then you need to check the multi-pin connector at the top of the blind flange of the fuel tank to see if there is any current going to the pump at all:
8. Fold back the boot floor covering.
9. Unscrew the black cap.
10. Disconnect the multi-pin connector.
11. Using a voltmeter or test lamp, check if there is a voltage of about 12 V between connector contacts 1 and 4 (brown and green/yellow wire). To take the measurement, your assistant must operate the starter (gear shift lever in neutral position, handbrake on).
12. If, despite the correct voltage, the pump does not work, it is faulty - dismantle and replace it.
13. If there is no voltage, the relay may be faulty. For information on checking it, see chapter Electrical equipment.
14. Other sources of malfunctions include: a defect in the wire to the relay or to the pump, a clogged or kinked fuel line, a clogged main filter.
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