Volkswagen Golf / Golf GTI / Golf Variant. Service manual - part 754

8

Fuel Pump

⇒ “8.1  Transfer Fuel Pump G6 , Checking”, page 81
⇒ “8.2  Fuel Pump Control Module J538 , Removing and Instal‐

ling”, page 116

8.1

Transfer Fuel Pump - G6- , Checking

⇒ “8.1.1 Fuel Pumps, Checking Function and Power Supply”,

page 81
⇒ “8.1.2 Fuel Pump, Checking Function and Power Supply, Ve‐

hicles with Engine Code CWVA”, page 84
⇒ “8.1.3 Fuel Pressure, Checking”, page 87
⇒ “8.1.4 Fuel Pressure, Checking, Vehicles with Engine Code

CWVA”, page 91
⇒ “8.1.5 Residual Pressure, Checking”, page 95
⇒ “8.1.6 Residual Pressure, Checking, Vehicles with Engine

Code CWVA”, page 99
⇒ “8.1.7 Fuel Delivery Rate, Checking”, page 104
⇒ “8.1.8 Fuel Delivery Rate, Checking, Vehicles with Engine Code

CWVA”, page 110

8.1.1

Fuel Pumps, Checking Function and

Power Supply

Special tools and workshop equipment required
♦ Trim Removal Wedge - 3409-
♦ Multimeter, for example Analog/Digital Multimeter - FLU83III-
♦ Connector Test Set - VAG1594D-
♦ Vehicle Diagnostic Tester
Test conditions:
• The battery voltage must be at least 11.5 V. Charge if neces‐

sary. Refer to ⇒  Electrical Equipment; Rep. Gr.  27 ; Battery;

Battery, Charging .

• Fuel Pump Control Module - J538- fuse OK. Refer to ⇒ Wiring

diagrams, Troubleshooting & Component locations.

• Fuel Pump Control Module - J538- is OK use the Vehicle Di‐

agnostic Tester .

Test sequence:

Note

The output diagnostic test mode checks the fuel pump function.

– Pay attention to all safety precautions. Refer to

⇒ “1 Safety Precautions”, page 1

 .

– Follow the guidelines for clean working conditions. Refer to

⇒ “3.1 Parking/Auxiliary Heater and Fuel System Clean Work‐

ing Conditions”, page 4

 .

– Connect the Vehicle Diagnostic Tester -1- as follows:
– Connect the diagnostic cable connector -2- to the diagnostic

connection inside the driver footwell.

– Switch the ignition on.
– Select the fuel pump output diagnostic test mode in OBD.
The fuel pump must now accelerate slowly up to the maximum

RPM.

Note

♦

The fuel pump runs very quietly.

♦

If the output diagnostic test mode is performed several times

in succession, it may be necessary to briefly start the motor

before repeating the output diagnostic test mode.

– Switch off the ignition.
If the fuel pump does not start:
Golf Sportsvan:
– Remove the right rear seat. Refer to ⇒  Body Interior; Rep. Gr. 

72 ; Rear Seats; Bench Seat / Single Seat, Removing and In‐

stalling .

– Partially loosen the cover -1- in the carpet at the separating

line -arrow-.

– Do not separate the cover completely from the carpet so that

later it will be installed correctly.

– Only loosen so far that the cover can be folded up.
– Fold up the cover in the direction of the -arrow-.
Golf and Golf Wagon:
– Remove the rear bench seat. Refer to ⇒  Body Interior; Rep.

Gr.  72 ; Rear Seats; Bench Seat / Single Seats, Removing

and Installing .

Continuation for All Vehicles:
– Unclip the right sealing flange cover -1- at the tabs -arrows-

using the -3409- .

– Unclip the grommet -1- downward out of the cover -2-.
– Guide the cover -2- on the wiring harness -3- toward the rear.

– Lift the tab -2- in the direction of the -arrow A- by using a finger

to reach between the floor panel and the fuel tank.

– At the same time, carefully pull the Fuel Pump Control Module

- J538- -1- out of the mount at the wiring harness -3- in the

direction of the -arrow B-.

– Remove the Fuel Pump Control Module - J538- toward the

inside between the fuel tank and the floor panel.

– Pull on the connector on the Fuel Pump Control Module - J538-

without pushing the locking mechanism to make sure it is

secure. Repeat the fuel pump functionality test if the connector

was not connected correctly.

– Release and remove the connector from the Fuel Pump Con‐

trol Module - J538- .

– Check the contacts on the connector and on the Fuel Pump

Control Module - J538- for damage.

– Check the voltage supply between contacts -3- and -4- using

the Multimeter . Refer to ⇒ Wiring diagrams, Troubleshooting

& Component locations.

– To do so, use the Connector Test Set - VAG1594D- .
– Switch the ignition on.
• Specified value: approximately battery voltage
If the specified value is not obtained:
– Locate and repair the open circuit according to the wiring dia‐

gram. Refer to ⇒ Wiring diagrams, Troubleshooting & Com‐

ponent locations.

If the specified value is obtained:

– Pull on the connector -1- without pressing the release to make

sure the connection is secure. Repeat the fuel pump function‐

ality test if the connector was not connected correctly.

– Release and disconnect the connector -1-.
– Check the contacts on the connector and on the fuel delivery

unit for damage.

– Check the wiring harness between the Fuel Pump Control

Module - J538- and the fuel delivery unit. Refer to ⇒ Wiring

diagrams, Troubleshooting & Component locations.

If no faults can be found:

WARNING

The fuel line is under pressure.
Fuel poses a risk of injury to the eyes and skin.
Wear protective eyewear and protective clothing to avoid injury

and contact with skin. Place a cleaning cloth around the con‐

nection  point  before  loosening  hose  connections.  Carefully

open the connection point to release the pressure.

– Drain the fuel tank. Refer to

⇒ “1.3 Fuel Tank, Draining”, page 35

 .

– Remove the fuel lines -1- from the flange. Disconnect the con‐

nector couplings. Refer to

⇒ “4.1 Connector Couplings, Disconnecting”, page 62

 .

Vehicles with Parking Heater:
– Remove the fuel line -2- to the Metering Pump - V54- for the

parking heater on the sealing flange.

– Open the lower clamp to do this.
– Carefully remove the fuel line -2-.

Continuation for All Vehicles:
– Open the locking ring using the Wrench - Fuel Sending Unit -

T10202- .

– Check if the wiring between the flange and fuel pump is con‐

nected.

– Inspect the contacts for damage.
If no Open Circuits are Found:
– If the fuel pump is faulty, replace the fuel delivery unit. Refer

to

⇒ “2.2 Fuel Delivery Unit/Fuel Level Sensor, Removing and

Installing”, page 52

 .

8.1.2

Fuel Pump, Checking Function and

Power Supply, Vehicles with Engine

Code CWVA

Special tools and workshop equipment required
♦ Trim Removal Wedge - 3409-
♦ Multimeter, for example Analog/Digital Multimeter - FLU83III-
♦ Connector Test Set - VAG1594D-
♦ Vehicle Diagnostic Tester
Test Conditions:
• The battery voltage must be at least 11.5 V. Charge if neces‐

sary. Refer to ⇒  Electrical Equipment; Rep. Gr.  27 ; Battery;

Battery, Charging .

• Fuse OK. Refer to ⇒ Wiring diagrams, Troubleshooting &

Component locations.