Fuel Pump, Checking: Notes

Test requirements 

• Fuses -13- and -14- (arrows) in E-box (plenum chamber, left) must be OK: Refer to SYSTEM WIRING DIAGRAM
  Fig 1: Identifying Fuses

  Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.
• Fuel Pump (FP) relays I and II must be OK:
  Fig 2: Identifying Fuel Pump Relays

  Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

1. Fuel Pump (FP) Relay -J17-, (Fuel Pump, right)
2. Fuel Pump (FP) 2 Relay -J49-, (Fuel Pump, left)

• Battery voltage must be at least 11.5 volts.
• All electrical consumers such as, for example, lights and rear window defroster must be switched off.
• For vehicles with automatic transmission, selector lever must be in P.
• Parking brake must be engaged or else daylight driving lights will be switched on.
• Ignition switched off.

Observe Safety Precautions.

Observe Clean Working Conditions.

Check function and voltage supply of fuel pumps.

Check delivery quantity, current pick-up, and check valves of Fuel Pumps (FP) FUEL PUMP, CHECKING) .

Checking function and voltage supply of fuel pumps 

Special tools and workshop equipment required 

• Multimeter VAG1526 or multimeter VAG1715
• Connector test kit VAG1594
• Wiring diagram

Test sequence, Fuel Pump (FP) -G6-, right 

Test sequence, Transfer Fuel Pump (FP) -G23-, left 

-- Remove Fuel Pump (FP) Relay -J17-, right, from relay carrier, position C20.

-- Bridge terminals 19d + 19e on relay carrier using appropriate adapter cables.

-- Switch ignition on.

Fuel Pump (FP) -G6-, right, must start up.

-- Switch ignition off.

If Fuel Pump (FP) runs: 

-- Check activation of Fuel Pump (FP) Relay -J17-, right, -1- according to wiring diagram: Refer to SYSTEM WIRING DIAGRAM

-- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.

-- Generate readiness code.

If Fuel Pump (FP) does not run: 

-- Remove bridge from terminal 19e.

-- Connect multimeter to terminal 19e + Ground (GND) of relay socket for voltage measurement.

-- Switch ignition on.

Specified value: at least 11.5 V

-- Switch ignition off.

If specified value is not obtained:

-- Locate and repair open circuit using wiring diagram: Refer to SYSTEM WIRING DIAGRAM

-- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.

-- Generate readiness code.

If specified value is obtained:

-- Bridge terminals 19d + 19e on relay carrier using appropriate adapter cables.

-- Disconnect 4-pin harness connector (arrow) left, next to fuel tank, at vehicle floor.

-- Connect multimeter to terminals 3 + 4 of connector for voltage measurement.

-- Switch ignition on.

Specified value: at least 11.5 V

-- Switch ignition off.

If specified value is not obtained:

-- Locate and repair open circuit using wiring diagram: Refer to SYSTEM WIRING DIAGRAM

-- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.

-- Generate readiness code.

If specified value is obtained:

-- Fuel Pump (FP) -G6- faulty, replace Fuel Pump (FP) unit, Fuel Pump (FP) unit, fuel gauge sender, and suction jet pump, removing and installing.

-- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.

-- Generate readiness code.

Test sequence, Transfer Fuel Pump (FP) -G23-, left 

-- Remove Fuel Pump (FP) 2 Relay -J49-, left, from relay carrier, position A6.

-- Bridge terminals 6d + 6e on relay carrier using appropriate adapter cables.

-- Switch ignition on.

Transfer Fuel Pump (FP) -G23-, left, must start up.

-- Switch ignition off.

If Fuel Pump (FP) runs: 

-- Check activation of Fuel Pump (FP) 2 Relay -J49-, left, -2- according to wiring diagram: Refer to SYSTEM WIRING DIAGRAM

-- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.

-- Generate readiness code.

If Fuel Pump (FP) does not run: 

-- Remove bridge from terminal 6e.

-- Connect multimeter to terminal 6e + Ground (GND) of relay socket for voltage measurement.

-- Switch ignition on.

Specified value: at least 11.5 V

-- Switch ignition off.

If specified value is not obtained:

-- Locate and repair open circuit using wiring diagram: Refer to SYSTEM WIRING DIAGRAM.

-- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.

-- Generate readiness code.

If specified value is obtained:

-- Bridge terminals 6d + 6e on relay carrier using appropriate adapter cables.

-- Disconnect 4-pin harness connector (arrow) left, next to fuel tank, at vehicle floor.

-- Connect multimeter to terminals 1 +2 of connector for voltage measurement.

-- Switch ignition on.

Specified value: at least 11.5 V

-- Switch ignition off.

If specified value is not obtained:

-- Locate and repair open circuit using wiring diagram: Refer to SYSTEM WIRING DIAGRAM.

-- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.

-- Generate readiness code.

If specified value is obtained:

-- Transfer Fuel Pump (FP) -G23-, left, faulty, replace Fuel Pump (FP) unit, Fuel Pump (FP) unit, fuel gauge sender, and suction jet pumps, removing and installing.

-- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.

-- Generate readiness code.