Fuel Injectors, Checking

Checking internal resistance
- Disconnect connector at the injector to be tested.







- Connect multimeter at valve for resistance measurement.
- Specified value: 12 - 13 ohm

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

If specified value is obtained:

Checking voltage supply

Test conditions
- Fuel Pump (FP) OK, checking. Testing and Inspection
- Fuse for fuel injectors OK.
- Disconnect connector at the injector to be tested.







- Connect VAG 1527B voltage tester as follows:

Harness connector terminal Measure to
1 Engine Ground

- Operate starter briefly (engine can also start).
- LED must light.

If LED does not light:
- Check wire connection between terminals 1 and fuse for injector valves for open circuit.
- Repair open circuit if necessary.

If LED lights:
- Check activation of fuel injectors.

Checking activation

Test requirement
- Internal resistance of injector OK:
- Slide back rubber grommet of fuel injector connector, but leave connector connected.







- Connect VAG 1527B voltage tester between sockets 2 (signal) and 1 (B+).
- Operate starter briefly (engine can also start).
- LED must blink.


NOTE: Voltage testers do not go out completely between activation's by the ECM, but rather continue to glow and then get slightly brighter during activation.


If LED does not blink:
- Connect VAG 1598131 test box at wiring harness to ECM, do not connect ECM.







- Check the following wire connections for open circuit and short circuit to Ground and B+:







- Repair open circuit or short circuit if necessary.

If wire connection is OK:
- Replace Engine Control Module (ECM).