Power Supply Checking

Ensure battery is fully charged (at least 12 volts) and fuel filter is in good condition.
Remove fuse No. 17 (15-amp) from fuse holder. See Figure . Connect remote control (VW 1348/3A) using adapter lead (VW 1348/3-2) and adapter cables from (VW 1594) between fuse No. 17, terminal No. 2 and battery positive (+) terminal. Vehicles with A/C, connect clip to remote starter aid connection in engine compartment.

NOTE: In noisy surroundings, second mechanic may be required to listen for pump operating noises under vehicle near fuel tank.

Operate remote control. Fuel pump must operate audibly. If fuel pump runs, check Fuel Pump (FP) relay. See FUEL PUMP RELAY in SYSTEM & COMPONENT TESTING article.
If fuel pump does not run, unscrew cover for fuel level sensor and fuel pump (under luggage compartment floor covering). Pull off connector for fuel pump and fuel level sensor. See Fig 1 .

Fig 1: Identifying Location Of Fuel Pump/Sending Unit In Luggage Compartment
Courtesy of AUDI OF AMERICA, INC.
Connect DVOM multimeter switched DC voltage range to harness connector terminals No. 1 (Green/Yellow wire) and No. 4 (Brown wire) using cables from (VAG 1594) adapter kit. See Fig 2 .

Fig 2: Identifying Fuel Pump/Sending Unit Harness Connector Terminal Numbers
Courtesy of AUDI OF AMERICA, INC.
Operate remote control. Voltage should be approximately battery voltage (12 volts/good battery). If specified value is not obtained, find a repair open or short to ground in wiring. See WIRING DIAGRAMS .
If specified value is obtained, remove fuel level sensor. Check wires from fuel level sensor housing to fuel pump for continuity with DVOM multimeter and adapter cables. Fix open in wiring, if necessary. See Fig 3 .
If no break in wiring is present, replace fuel pump.

Fig 3: Identifying Fuel Pump/Sending Unit Wiring Harness To Pump

Courtesy of AUDI OF AMERICA, INC.