Checking function and voltage supply of fuel system pressurisation pump G6 — VW

Checking function and voltage supply of
fuel system pressurisation pump
G6
Special tools and workshop equipment required
Removal wedge
3409
Multimeter e.g.
hand-held multimeter
V.A.G 1526E
Auxiliary measuring set
V.A.G 1594C
Test instrument adapter/DSO (5-pin)
VAS 5565
Vehicle diagnostic tester
Test prerequisites
Battery voltage must be at least 11.5 V. If necessary, charge battery
Electrical system
Rep. gr.
27
Battery; Charging battery
.
Fuse for
fuel system pressurisation pump
G6
OK
Current flow diagrams, Electrical fault finding and Fitting locations
.
Test sequence:
Note
Function of fuel pump is checked using final control diagnosis.
Observe safety precautions
Chapter
.
Observe rules for cleanliness
Chapter
.
Observe safety precautions when working on natural gas system
Chapter
.
Connect
vehicle diagnostic tester
1
as follows:
Connect diagnosis cable connector
2
to diagnostic connection in driver footwell.
Switch ignition on.
Press following buttons on display one after the other:
Vehicle self-diagnosis
Engine electronics
Final control diagnosis
Electric fuel pump
►
Button
The fuel pump must now run slowly up to maximum speed.
Note
The fuel pump runs very quietly.
If the final control diagnosis is to be carried out several times in succession, it may be necessary to start the engine briefly before repeating the final control diagnosis.
Switch off ignition.
If fuel pump does not run:
Remove bench seat
General body repairs, interior
Rep. gr.
72
Rear seat; Removing and installing bench seat / individual seats
.
Unclip cover
1
at retaining tabs using
removal wedge
3409
.
Check that connector
arrow
is fitted securely by pulling connector without pressing catch. If connector was not inserted correctly, repeat functional check of fuel pump.
Check contacts of connector for damage.
Check that connector
1
is fitted securely by pulling connector without pressing catch. If connector was not inserted correctly, repeat functional check of fuel pump.
Release and unplug connector.
Check contacts on connector for damage.
Connect
test instrument adapter/DSO (5-pin)
VAS 5565
to connector and fuel delivery unit.
Connect
multimeter
V.A.G 1526E
to cables
1
and
5
of
test instrument adapter/DSO (5-pin)
VAS 5565
.
Initiate final control diagnosis again and measure voltage at fuel pump.
Specification: approx. battery voltage.
If the specification is not attained:
Locate and eliminate open circuit referring to current flow diagram
Current flow diagrams, Electrical fault finding and Fitting locations
.
If specification is attained:
Remove fuel delivery unit
Chapter
.
Check that electrical wires between flange and fuel pump are connected.
Check contacts for damage.
If no open circuit can be found:
Fuel pump is defective, renew fuel delivery unit
Chapter
.