Testing fuel pump relay -J17 and actuation — AUDI

ADW
Note:

Fitting location of fuel pump relay: On central electrics below dash panel on left, contact point 6

Special tools, testers and auxiliary equipment required

Voltage tester V.A.G 1527 B
Adapter wire set V.A.G 1594 A

Testing operation of fuel pump relay

Remove trim panel at the bottom of the right A pillar and the right entrance plate in the area of the front door

=> General Body Repairs; Repair Group 70; Trim Panel; Removing and installing trim panels of A pillar and inner entrance plate
General Body Repairs
Trim Panel
Removing and installing trim panels of A pillar and inner entrance plate

Turn back carpeting in the front right footwell (cut open left pre-punched seam with a knife, if necessary).

Remove the screws for the cover of the electronics box -arrows-.
Carefully detach the top and bottom cover part

Pull out the fuses in the black holder -1- and in the brown holder -2-.

Take off the cover of the left fuse holder.

Take out fuse 17 and connect voltage tester V.A.G 1527 B between earth and the rear contact for fuse 17 using auxiliary wires from V.A.G 1594.
Operate starter briefly.
The fuel pump relay should be heard and felt to operate; the LED should come on.

If the relay does not operate:

Test actuation => Page
24-36

If the relay operates, but the LED does not come on:

Referring to the current flow diagram remove the fuel pump relay and test the connection from fuse 17 to contact 30 in contact position 6 for open circuit.
Replace the relay plate, if necessary.
If no open circuit can be found, continue the test.
Re-insert the fuel pump relay and fuse 17.

Connect voltage tester V.A.G 1527 B with auxiliary wire from V.A.G 1594 A between earth and contact -1- for fuse S73 in the brown holder.
Operate starter briefly.
The fuel pump relay should be heard and felt to operate; the LED should come on.

If the relay does not operate:

Test actuation => Page
24-36

If the relay operates, but the LED does not come on:

Repeat the test at contact -2- for fuse S73 in the brown holder.

If LED still does not light:

Disconnect fuel pump relay.
Referring to the current flow diagram test the wiring connection between fuel pump relay base contact 31 and fuse S73 in the brown holder for open circuit
If no open circuit can be found, continue the test.

Re-insert the fuel pump relay and fuse 17 in the brown holder.

Connect voltage tester V.A.G 1527 B with auxiliary wire from V.A.G 1594 A between earth and contact -1- for fuse S72 in the black holder.
Operate starter briefly.
The fuel pump relay should be heard and felt to operate; the LED should come on.

If the relay does not operate:

Test actuation => Page
24-36

If the relay operates, but the LED does not come on:

Repeat the test at contact -2- for fuse S72 in the black holder.

If LED still does not light:

Disconnect fuel pump relay.
Referring to the current flow diagram test the wiring connection between fuel pump relay base contact 30 and fuse S72 in the black holder for open circuit

Rectify open circuit, if necessary
If the wiring connection is OK, replace the fuel pump relay.
Re-insert the fuel pump relay and fuse S72 in the black holder.

Testing the power supply and actuation of the fuel pump relay

Take off the cover of the auxiliary relay carrier 1 in the left of the plenum chamber.
Disconnect fuel pump relay.

Testing power supply

Switch the ignition on.

Set hand held multimeter V.A.G 1526 to voltage measuring range (20 V direct current) and connect it as follows:

Contacts · Specification
28 + 34 · approx. battery voltage
32 + 34 · approx. battery voltage

Switch off ignition.

If the specified values are not obtained:

Test the wiring.

=> "Current Flow Diagrams, Electrical Fault Finding and Fitting Locations" binder

Testing actuation

Connect voltage tester V.A.G 1527 B as follows:

Fuel pump relay base
Contact · Contact
28 · 29

Switch the ignition on.
The LED should come on for about 1 second

Operate starter.
The LED should come on and remain on during the starting operation.

If the LED does not come on:

With the ignition switched off, connect test box V.A.G 1598/18 to connector for engine control unit => Page
24-16
.

Test for open circuit and short to positive or earth in the following wiring connections:

Fuel pump / relay base / Contact · Test box V.A.G 1598/18 / / Socket
29 · 31

Rectify any open/short circuit as necessary.
If the actuation and wiring connection is OK, replace the fuel pump relay.