Fuel Pump Relay, Checking

Fuel Pump Relay, Checking







NOTE: The fuel pump relay is located on the central electrical panel in the right-side footwell, in relay position 6.


Checking voltage supply
- Remove fuel pump relay -J17-.
- Switch ignition on.







- Connect multimeter US 1119 (Fluke 83 or equivalent) and check for voltage between relay terminals:
- 28 (B+, terminal 15) and 34 (Ground)
- 32 (B+, terminal 30) and 34 (Ground).
Specified value: approx. Battery Positive Voltage (B+)

If voltage is not OK:
- Check wiring for open circuit.

Checking Fuel Pump Relay Actuation







- Connect VAG1527B LED voltage tester between relay terminals 28 (B+) and 29 (Ground from ECM).
- LED must light up for approx. 1 second and then go out.
When operating starter, LED must light up continuously.


NOTE: LED voltage testers with little current draw do not completely go out after 1 second, but will continue to glow dimly until the starter motor is operated.


If LED does not light up, check wiring as follows:
- Connect VAG1598/19 test box to Engine Control Module (ECM) harness connector. Refer "Scan Tool Testing/Scan Tool Connecting and Initial Checks/VAG1598/19 Test Box, Connecting" Testing and Inspection







- Connect multimeter US 1119 (Fluke 83 or equivalent) and check for continuity between relay terminal 29 and test box socket A4.
- If there is no continuity:
- Check wiring for open or short circuit.

If there is no open circuit, and LED does not light up:
- Replace Engine Control Module (ECM), and generate new readiness code. Refer to "Monitors, Trips and/or Drive Cycle (Readiness Code)/Generating, Readiness Code" Testing and Inspection

If wiring harness and actuation of fuel pump relay are OK:
- Replace fuel pump relay.
- Check readiness code. If DTC memory has been erased, generate new readiness code.
Refer to "Monitors, Trips and/or Drive Cycle (Readiness Code)/Generating, Readiness Code" Testing and Inspection
Refer to "Monitors, Trips and/or Drive Cycle (Readiness Code)/Checking, Readiness Code" Testing and Inspection

Checking function of fuel pump relay -J17-
- Remove cover for fuse panel on right-side A-pillar.







- Connect VAG1527B LED voltage tester between upper terminal for fuse 1 or fuse 3 (located at blue fuse holder, fourth row from top) and Ground.
- Operate starter motor for a few seconds.
- Fuel pump relay should be actuated
- LED should light up

If LED does not light up, but fuel pump relay is actuated:
- Repeat test using lower fuse terminals.

If LED still does not light up:
- Remove fuel pump relay from central electrical panel in right-side footwell, relay position 6.







- Check wiring for open circuit between:
- Relay panel terminal 30 (relay position 6) and fuse 1
- Fuse 3 and relay panel terminal 31 (Ground)

If there is no open circuit:
- Replace fuel pump relay.

If fuel pump relay was not actuated:
- Check relay actuation circuit.

If voltage supply and relay actuation circuit are OK:
- Replace fuel pump relay.
- Check readiness code. If DTC memory has been erased, generate new readiness code.
Refer to "Monitors, Trips and/or Drive Cycle (Readiness Code)/Generating, Readiness Code" Testing and Inspection
Refer to "Monitors, Trips and/or Drive Cycle (Readiness Code)/Checking, Readiness Code" Testing and Inspection