Fuel Pump, Testing (Electrical Test)

Fuel Pump, Testing (Electrical Test)

Special tools and equipment







- VAG 1348/3A with VAG 1348/3-2
- VAG 1526 A
- VAG 1594 A

Requirements for test
- Battery voltage not less than 12.7 V
- Fuse in fuse holder -S228- OK (plug-in position No. 28)







- Fuel pump relay (arrow) OK (located at plug-in position No. 1 in nine-way relay carrier behind storage compartment on driver's side)
- Fuel filter OK
- Ignition switched off

Test sequence
- Open fuse box cover on the left side of the instrument panel.
- Pull Fuse in fuse holder -S228- off plug-in position 28 of fuse carrier (left row, 5th large fuse from the top).







- Connect remote control VAG 1348/3A using adapter cable VAG 1348/3-2 to right-hand fuse socket terminal of Fuse in fuse holder -S228- (plug-in position No. 28).
- Connect clamp to vehicle battery positive (+).
- Press remote control switch.
- Pump should start running (audible when standing close to fuel tank).


NOTE: The fuel pump runs very quietly. Where possible, avoid noisy surroundings for this test.


If pump does not start running:







- Remove rear seat bench.
- Detach cover for flange -arrows- (right side).







- Carefully disengage and remove electrical harness connector -1- (right side of vehicle).







- Connect multimeter (voltage range) between contacts 1 and 4 of connector.
- Press remote control switch.
- Specification: approx. battery voltage

If the specification is not reached:
- Repair open circuit in wiring according to wiring diagram.

If the specification is obtained, even though the fuel pump did not run:
- Remove fuel delivery unit.







- Check that the electrical wires between flange and fuel pump are connected and test for continuity.

If no malfunction is detected in the wires, fuel pump is malfunctioning. Replace fuel delivery unit.
- Install fuel delivery unit.