Checking the fuel pump relay (Audi A4 B6)

Vehicles with an airbag have a collision fuel shut-off device. This device is designed to reduce the risk of fire after a collision. To do this, the fuel pump is switched off using a relay. In addition, this device improves comfort when starting the engine. When the door is opened, power is supplied to the pump for 2 seconds so that pressure is built up in the fuel system.

If the fuel pump does not work, check the fuel pump relay. This relay is located in slot 1 of the relay panel behind the driver's side storage compartment.



1. Remove the fuel pump fuse (S228) from socket 28. This fuse is located in the fuse box on the left side of the instrument panel.

2. Connect an LED voltage tester between the housing and one of the two fuse contacts.

3. Operate the starter. You should hear the relay operate. The tester LED should also light up.

4. If the LED does not light even though the relay core is pulled in, repeat the test with the other fuse contact.

5. If the LED still does not light, check the wires according to the circuit diagram. If necessary, eliminate the wire break.

6. If the wires and power are OK, replace the relay.

The original publication in its entirety is posted on the website audimanual