Checking fuel pump (electrical test) — AUDI

🧭 Before you start

Strip out the rear of the cabin: rollover bars, rear shelf, side trim, the control unit bracket and finally the convertible roof unit. Lift the insulating mat, remove the right-hand flange cover and unplug the flange connector. Wire the pump to battery positive through V.A.G 1348/3A and adapter V.A.G 1348/3-3, earth contact 5 to the body and listen for it running. If it does not run, drain the tank if needed, disconnect the lines, remove the locking ring and flange and check the internal connector and wiring; with no wiring fault, renew the fuel delivery unit and leak-check the tank.

Fits: platform code 42

• Opens: fuel
• Special tools named: V.A.G 1348, V.A.G 1348/3, V.A.G 1348/3A
• Renewed: fuel delivery unit

Don't miss

• Tape off the second contact of adapter V.A.G 1348/3-3 to prevent a short circuit.
• The pump runs very quietly; test in a quiet workshop so you can actually hear it.
• The tank must be no more than 1/4 full before disconnecting fuel lines at the flange.
• There may be 2 or 3 fuel lines on the flange depending on version; label them before removal.
• After refitting, check the fuel tank for leaks before the convertible roof unit goes back in.

Written for this job from the workshop steps below · TorqFix editorial.

🔧 Engine codes this applies to

📐 23 workshop diagrams for AEH

Real factory drawings for this job — timing marks, bolt locations and routing. Locked in the free view.

📋 Procedure

1. Observe test conditions .
2. Move seats as far forward as possible and tip down backrests.
3. ⚠ To prevent irreparable damage to the electronic components when disconnecting the battery:Observe notes on procedure for disconnecting the battery. — With ignition switched off, disconnect earth cable (1) at battery Electrical system27.
4. Slacken nut a few turns and disconnect battery clamp (2) from positive battery terminal.
5. Remove rollover bars General body repairs, interior69.

6. Remove rear shelf 70.
7. Remove side trim 70.
8. Unscrew positive wire (4).
9. Unplug electrical connectors (3) at connector point, detach connector point from bracket for control units and move connector point to the side.
10. Detach relay and fuse holder (rear right) from bracket for control units (arrows) and move relay and fuse holder aside. [Note: Disregard (items 1, 2, 5).]
11. Unplug electrical connectors for control units, unbolt bracket for control units (arrows) and remove bracket from vehicle.
12. Pry electrical wiring harness off base of back panel using removal lever80-200 and move harness clear.
13. Remove convertible roof unit 61.
14. Fold back insulating mat above cover for fuel tank flange.
15. Unscrew bolts (1 ... 4) and remove cover for flange on fuel tank (right-side).
16. Unplug electrical connector (arrow) on flange (right-side). [Note: Disregard (items 1, 2, 3).]
17. Connect remote controlV.A.G 1348/3A for V.A.G 1348 to contact (1) using adapter cable V.A.G 1348/3-3 and test lead from auxiliary measuring setV.A.G 1594D.
18. Tape off 2nd connector contact of adapter cable V.A.G 1348/3-3 with insulating tape (arrow) to prevent short circuits.
19. Connect contact (5) to vehicle body (earth) using a test lead from auxiliary measuring setV.A.G 1594D.
20. Connect crocodile clip to positive battery terminal "“+”".
21. While checking fuel pump, re-connect battery earth clamp to negative battery terminal "“–”" by hand.
22. Press remote control switch V.A.G 1348/3A. [Note: The fuel pump runs very quietly. Where possible, avoid noisy surroundings when testing the fuel pump.]
23. ⚠ Risk of injury caused by fuel.To reduce the pressure in the fuel system, wrap a clean cloth around the connection and carefully loosen the connection.Large amounts of fuel can escape.The fuel tank must not be more than 1/4 full when disconnecting the fuel lines, otherwise a large amount of fuel will escape. — Drain fuel tank if necessary .
24. Press release tabs and disconnect fuel lines (1, 2 and 3) on flange (right-side). [Note: There can be 2 or 3 fuel lines, depending on version.]
25. Remove locking ring on flange (right-side) using wrench T10202.
26. Remove flange and seal for fuel delivery unit from opening in fuel tank.
27. Press release tab and detach fuel line (1) on inside of flange.
28. Check whether electrical connector (4) for fuel pump is connected, or check for continuity in wiring between flange and fuel pump as necessary. [Note: Disregard (items 2, 3).]
29. If no wiring fault is detected: fuel pump is defective. Renew fuel delivery unit.
30. Install fuel delivery unit .
31. Check fuel tank for leaks .
32. Install convertible roof unit 61.
33. Connect battery and perform steps required after connecting battery Electrical system27).

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