With Manufacturer's Scan Tool

Fuel Injectors, Checking

Special tools and workshop equipment required:

- V.A.G 1526 A Multimeter.
- V.A.G 1527 B Led voltage tester.
- V.A.G 1594 A Connector test kit.
- V.A.G 1598/31 Test box.

Procedure

- Remove engine cover -arrow-.

Checking internal resistance

- Remove connector on fuel injector to be checked.

- Connect multimeter to fuel injector to measure resistance.
- Specified value: 12...13 Ohm (at room temperature)

If specified value is not obtained:
- Replace fuel injector.

If specified value is obtained:

Checking power supply

Test requirements:

- Fuse for injectors OK.
- Fuel pump relay OK. Testing and Inspection

NOTE: The fuel injectors receive their power supply via the fuel pump relay.

- Remove connector on fuel injector to be checked.

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

Connector Measure to
terminal

1 Engine ground (GND)

- Operate starter briefly.
- LED should light up.

If the LED does not light up:
- Check wiring connection between terminal 1 and fuse for fuel injector for open circuit.
- Repair any open circuit or wiring concerns.

If the LED lights up:

Checking activation

Test requirements:

- Internal resistance of the valve OK.
- Push back rubber grommet of connector on fuel injector but leave connector attached.

- Connect LED voltage tester V.A.G 1527 B between terminals 2 (signal) and 1 (B+).
- Operate starter briefly.
- LED should flash.

NOTE: Voltage testers with a low current draw continue to glow faintly between activation from the Engine Control Module (ECM) (rather than extinguishing completely) and become slightly brighter when activated.

If LED does not flash:
- Connect test box V.A.G 1598/31 to wiring harness for Engine Control Module (ECM); do not connect Engine Control Module (ECM).

- Check for open circuit, short to positive, or short to ground in following wiring connections:

- Repair any open/short circuit as necessary.

If the wiring is OK:
- Replace Engine Control Module (ECM).