Audi Workshop Service and Repair Manuals

Checking fuel pump (electrical test)

Special tools and workshop equipment required

t	Spanner for union nuts -3217-

t	Adapter cable -V.A.G 1348/3-2-

t	Remote control -V.A.G 1348/3 A-

t	Hand-held multimeter -V.A.G 1526 A- or -V.A.G 1526 B-

t	Adapter set -V.A.G 1594 A- or -V.A.G 1594 C-

Test requirements

l  Battery voltage at least 12.5 V l  Fuse No. 18 OK l  Fuel pump relay -J17--arrow- on 6-position relay carrier, position 5 in driver's footwell (left-side) OK; checking → Injection and ignition system; Rep. Gr.24. l  Fuel filter OK l  Ignition off.

Test sequence –  Open fuse box cover on instrument panel (left-side). –  Detach fuse S18 from fuse carrier (3rd fuse in 4th row as seen from top). –  Connect remote control -V.A.G 1348/3 A- with adapter cable -V.A.G 1348/3-2- to left-hand terminal of fuse socket S18. –  Connect clamp to vehicle battery (+). –  Press remote control button. l  Pump should start running audibly.   Note The fuel pump runs very quietly. Where possible, avoid noisy surroundings for this test.

If pump does not start running: –  Fold down rear seat bench. –  Fold back lining under rear set. –  Turn fuel delivery unit cover in -direction of arrow- and detach.

–  Carefully release electrical connector from flange -arrow- and unplug.

–  Connect multimeter between contacts -1- and -4- to measure voltage. –  Press remote control button. l  Specification: approx. battery voltage If specification is not reached: –  Eliminate open circuit in wiring (refer to current flow diagram).

If reading matches specification although no pump running noise can be heard: –  Remove the fuel delivery unit → Chapter. –  Check that the electrical wires between flange and fuel pump are connected and test for continuity. If no fault is found in wiring, fuel pump is defective. Renew fuel delivery unit. –  Install fuel delivery unit → Anchor.