Checking the fuel pump relay (VW Transporter T4)

Fuel Pump Relay and Fuse Location

The fuel pump relay needs to be checked if the fuel pump does not work.

1. Check fuse #18 of the fuel pump. Replace if faulty.

2. Remove the fuel pump relay from the relay board (relay location #12).

3. Turn on the ignition.

4. Connect the LED indicator:

• to contact 6 and ground (-);
• to contact 2 and ground (-);
• to contact 6 and 4.

The diode should light up. Otherwise, find the break in the electrical circuit and fix it.

5. Connect the LED indicator to contacts 2 and 3 using an additional wire.

6. Turn on the ignition. The LED should light for 1 sec., otherwise check the wiring to the Digifant control unit according to the wiring diagram (see subsection 10.20.9). Fix the break or replace the control unit.