FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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With Manufacturer's Scan Tool




Special tools and equipment
- Scan tool VAG 1551 or vehicle system tester VAG 1552 with cable VAG 1551/3
- Test box VAG 1598/31
- Hand multimeter VAG 1526 or multimeter VAG 1715
- VAG 1527B Voltage tester
- Adapter set VAG 1594
- Wiring diagram

Check conditions
- Engine speed (RPM) sensor must be OK, checking. Testing and Inspection
- Fuel pump relay must be OK







- Fuses 28 and 32 must be OK.

Test sequence
- First check the activation of the injectors via Output Diagnostic Test Mode. Refer to "Scan Tool Testing/Output Diagnostic Test Mode (DTM) Initiating" Testing and Inspection

If one or more injectors do not click:

Checking resistance of injectors







- Check resistance of injectors between contacts.

Specification: 12 - 17 ohms


NOTE: The resistance figures are valid for approx. 20 °C. At higher temperatures the resistance figures will increase.


If the specification is not attained:
- Replace faulty injector.

Checking voltage supply
- Pull connectors off injectors







- Connect diode test lamp to contact 1 and Ground of relevant injector connector.
- Operate the starter and check the voltage supply for the injector.

- The LED must light up

If the LED does not light up:
- Switch off ignition.
- Check wire between 2-pin connector contact 1 and fuel pump relay (J17) for open circuit using wiring diagram.
Wire resistance: max. 1.5 ohms

Checking activation and voltage supply
- Pull connectors off injectors.
- Connect the VAG1527B Voltage tester to the connector contacts of the injector to be tested using adapter cables from VAG 1594.
- Operate starter and check activation for injector.

- The LED must flicker

If the LED does not flicker:
- Switch off ignition.







- Connect test box VAG 1598/31 to control module wiring harness. The engine control module remains disconnected.







- Check the wiring between the test box and connector for open circuit, short circuit to Ground or positive using wiring diagram:
Injector 1: contact 2 + socket 96
Injector 2: contact 2 + socket 89
Injector 3: contact 2 + socket 97
Injector 4: contact 2 + socket 88
Wire resistance: max. 1.5 ohms

If no fault can be found in the wiring:
- Replace engine electronics control module.