Fuel Pump (FP) Control Module, Checking, Vehicles With 4-Cyl. TFSI Engine

Fuel Pump (FP) Control Module, Checking, Vehicles with 4-Cyl. TFSI Engine

Special tools, testers and auxiliary items required

• Hand-Held Multimeter (V.A.G 1526C)

• Connector Test Set (V.A.G 1594C)

• Adapter Cable (V.A.G 1598/39)

• Test Box (V.A.G 1598/42)

Test Conditions

• Battery voltage min. 12.5 V.

• Fuse on Fuse Panel (S228) (position 28) OK.





• Ignition switched off.

Check voltage supply for Fuel Pump (FP) (from Fuel Pump (FP) Control Module (J538))

- Remove rear seat bench.

- Remove cover - arrows - for right locking flange.





- Fold the protective boot back.

- For voltage testing, connect the Hand-Held Multimeter (V.A.G 1526C) with measuring probes and connector adapters from the Connector Test Set (V.A.G 1594C) between clamp - 1 - and - 4 -, as shown in the illustration. The connector remains connected.





• Connector sockets are numbered respectively on the rear side of the connector.

- Start engine.

• Specified value at start and in idle: 4 to 5.7 V.

- Depress accelerator pedal completely and then release it (brief throttle burst).

• Specified value: The voltage value must first rise slightly, then fall and then rise again to the value previously read.

If the reading does not result as described:

- Check voltage supply and activation of the Fuel Pump (FP) Control Module (J538).

Check voltage supply for Fuel Pump (FP) Control Module (J538)





- Remove Fuel Pump (FP) Control Module (J538). Refer to => [ Fuel Pump Control Module ] Service and Repair.

- Disconnect electrical harness connector - arrow - on Fuel Pump (FP) Control Module (J538).

- Connect multimeter between terminal - 3 - and - 4 - of harness connector for voltage measurement.





- Switch on ignition.

• Specified value: Approximately battery voltage.

If specification is not obtained:

- Repair open circuit in wiring according to wiring diagram.

Check activation of Fuel Pump (FP) Control Module (J538)

- Remove protective cap.

- For voltage testing, connect the multimeter with measuring probes and connector adapters from the Connector Test Set (V.A.G 1594C) between clamp - 4 - and - 5 -, as shown in the illustration. The electrical connection remains connected.





• Connector sockets are numbered respectively on the rear side of the connector.

- Start engine.

• Specified value at start and in idle: Approximately 5.0 V

- Depress accelerator pedal completely and then release it (brief throttle burst).

• Specified value: The voltage value must first rise slightly, then fall and then rise again to the value previously read.

If the reading does not result as described:

- Switch off ignition.

- Connect Test Box (V.A.G 1598/42) to wiring harness with Adapter Cable (V.A.G 1598/39-1) or Adapter Cable (V.A.G 1598/39-2); engine control module (ECM) remains connected. Clamp test box Ground (GND) clip to battery negative terminal.





CAUTION!
To avoid damaging electronic components, set measuring range before connecting test leads and observe all test requirements.

- Check the following wire connection for open circuit and short circuit to Ground (GND) and B+:









- Repair wiring open circuit or short circuit according to wiring diagram.

If no malfunctions are detected:

- Replace the Fuel Pump (FP) Control Module (J538 ).