Ere Tis,
Requirements for test:
Battery voltage not less than 12.7 V
Fuse S1 OK (in fuse box, blue fuse carrier ST4)
Fuel pump relay OK (on central electrics unit in electronics box; passenger's footwell, relay position 6).
Testing:
Fuel filter OK
Ignition switched off
Checking voltage supply
Remove fuse holder cover in driver’s footwell
Pull fuse No. S1 out of fuse carrier ST4 in fuse box.
ST4 - blue fuse carrier
Connect jumper lead with momentary switch to lower terminal of socket for fuse No. S1 in fuse carrier ST4 -arrow 1-.
Connect clamp to positive battery supply (e.g. socket of 60 Amp fuse -arrow 2- at top of fuse box).
Press remote control switch.
Pump should start running audibly.
Note:
The fuel pump runs very quietly. Where possible, avoid noisy surroundings for this test. If necessary, perform the test with a 2nd mechanic.
If pump does not start running:
Remove cover for fuel gauge sender and fuel delivery unit (right side) under floor covering in boot -arrows-.
If pump does not start running:
Remove cover for fuel gauge sender and fuel delivery unit (right side) under floor covering in boot
Release 4-pin connector -arrow- and unplug.
Connect multimeter (voltage range) between contacts 1 and 4 of connector.
Press remote control switch.
Specification: approx. battery voltage
If the specification is not obtained:
Locate and eliminate open circuit using current flow diagram:
If the specification is obtained, even though the fuel pump did not run:
Remove fuel delivery unit
Check if the electric wires between flange and fuel pump are disconnected or broken (test continuity).
If no fault is detected in the wiring:
Fuel pump is defective. Renew fuel delivery.
Testing current draw
Test requirement:
Supply voltage for fuel pump OK
terminal of socket for fuse No. S1 in fuse carrier ST4 -arrow 1-.
Connect clamp to positive battery supply (e.g. socket of 60 A fuse -arrow 2- at top of fuse box).
Connect multimeter with current clamp to connecting lead for remote control switch.
Press remote control switch.
Measure the current draw of the fuel pump.
Specification: approx 8 A
If the specification is not attained:
Note:
If the indicated current draw is 4 amps, this means the fuel pump is running dry (without fuel).
Meter reading---------------- Cause of fault------------------------------------- Rectification
approx. 4 A -------------------- Tank empty --------------------------------------- Fill up with fuel
------------------------------------ Fuel delivery unit incorrectly installed ---- Check installation of fuel delivery unit
----------------------------------- Baffle housing leaking -------------------------- Perform leak test on baffle housing
------------------------------------ Fuel gauge sender 2 incorrectly installed - Check installation of fuel gauge sender 2
0 A ------------------------------- Fuel pump defective -------------------------- Renew fuel delivery unit
__________________
Conan (the Librarian)
Watch it if you dare
Currently,
2000 S8, Merlin Purple, Leather Pack 1, Winter Pack 1, SPAX adjustable suspension, AP Racing 6 pot front caliper, 385mm fully floating disks, EBC Yellow Stuff Pads, Black Diamond grooved rear disks and predetor pads, D2 Doctors Brake Block.
1997 4.2 A8SQ - the Projekt. 12 years and ongoing!
1997 4.2 A8SQ - Ming Blue. Restoration sat waiting; saved from the Scrapyard
2003 C5 Allroad 4.2Q - Cobolt Blue. Towing car. Laid up awaiting manual conversion.
2005 C5 Allroad 2.5TDi FE - Grey - Workhorse.
2015 Q3QS SLine - Daytona Grey. Lots of extras! Long Haired Admirals cutter.
Previously
2003 C5 A6 1.9TDI FWD - Loaner from D2 Doctor Lifex
1997 S8 - Ming Blue. Loaned out and written off. I loved that car. My first engine swap after cambelt failure.
1996 4.2 A8SQ - Ming Blue. 178k on a cambelt! Trader's 8. Delivered to A8Parts at Lifex.
2003 2.8 A8SQ - powder blueish. Fill in for a while. Sold on.
1998 1.8T A4 Avant FWD. Ming Blue (there's a theme here), PEX for the 97 S8.
And a list of non VAG going back 40 years before I saw the light. 
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